Schedule updates: the monthly check

A schedule update is the contractor telling you, once a month, where the job really stands and when it will finish. Many owners look only at the finish date, which is the last thing to trust. Before you believe any forecast, check that the update was built honestly: the right data date, real actuals, logic intact, and a narrative that explains what moved and why. This lesson gives you a monthly check you can run in about two hours.

Learning outcomes

• Explain what a monthly schedule update is, what the data date does and what CCDC 2-2020 GC 3.4 asks the contractor to do.
• Run a four-part owner's check on an update: integrity, progress, logic and critical path, and narrative.
• Spot the common distortions: actuals after the data date, out-of-sequence progress, new constraints and quiet logic changes.
• Track float erosion across updates and decide when to ask for a recovery schedule.

The lesson

What an update is, and what it is not

The baseline is the approved plan. An update is a copy of that plan with progress recorded to a cut-off date and the remaining work rescheduled from it. Under CCDC 2-2020 GC 3.4, the contractor must give the Owner and Consultant a construction schedule before the first application for payment, monitor progress against it, and update it monthly unless the Contract Documents say otherwise. It must also tell the Consultant about schedule revisions that follow from Contract Time extensions under Part 6. The owner's Supplementary Conditions and Division 01 specification add the detail: native files, a narrative, a deadline and the right to reject.

An update is not a new baseline. The baseline stays fixed so you can measure against it. Changes to durations, logic or calendars are revisions: they must be disclosed and, if significant, accepted. An update that silently rewrites the plan makes every later comparison meaningless.

The data date

The data date (status date in Microsoft Project) splits the schedule in two. Everything before it is history: actual starts, actual finishes, and remaining durations as at that date. Everything after it is forecast. Two rules follow, and the GAO Schedule Assessment Guide states both: no actual date can sit after the data date, and no unfinished work can be forecast to happen before it [2][3]. An activity that was supposed to start last week and has no actual start is not "on time"; it is late, and the software should push it to the data date or later.

Agree the cut-off once and keep it. On Northgate the data date is the last day of each month, the date of the payment application under GC 5.2, so the schedule and the payment application describe the same work.

Retained logic or progress override

When an activity starts before its predecessor finishes, the schedule has out-of-sequence progress, and the software needs a rule for the remaining work. In Oracle Primavera P6 the rule sits on the Settings tab of the Schedule dialog. Retained Logic makes the remaining duration wait for the predecessors to finish. Progress Override ignores the logic for that activity and lets it carry on. A third option, Actual Dates, uses actual dates in the forward and backward passes [4]. Microsoft Project has comparable choices in its scheduling options.

Retained Logic is usually the conservative choice: it assumes the reason for the link still holds. Progress Override suits a link that was never real, but it can hide a dependency and shorten the critical path. The GAO guide expects the update narrative to say which method was used and to disclose any change to scheduling settings between periods [2]. Your check is simple: compare the settings with last month's. If they changed, ask why.

The owner's monthly check

Run the check in four parts, in order. There is no point reading the critical path if the data date is wrong.

For part 3, a schedule comparison tool helps, but two layouts side by side will do. The DCMA 14-point assessment gives useful screening thresholds for logic quality: missing logic on no more than 5% of incomplete activities, no leads, lags on no more than 5% of relationships, at least 90% finish-to-start links, hard constraints on no more than 5%, and no invalid dates [5]. Treat them as prompts, not pass marks.

Float erosion

Total float on the path to the contract completion date is the single most useful number in a monthly update, if you watch its trend. One month of float loss can be noise. Three months in a row is a pattern, and the right time to ask for a recovery plan is while there is still float to protect, not after it has gone negative. GAO's checklist pairs significant delays with recovery plans that are put in place once approved [3].

Who owns float depends on the contract and any float clause in the Supplementary Conditions. The owner does not need to settle that to use the trend as a warning.

Northgate worked example

Northgate Distribution Centre (fictional) is a 12,000 m² tilt-up warehouse in Vaughan, Ontario, for Northgate Logistics Inc. (fictional). Halvorsen Builders Ltd. (fictional) submits its P6 schedule as XER files; the owner's scheduler imports each one beside the baseline NDC-BL00 in the owner's NDC.SUB branch and carries the milestone forecasts into the owner's Microsoft Project master. See the Northgate fact sheet.

Halvorsen's August 2027 update, NDC-UP06, has a data date of Tuesday August 31, 2027, and arrived on Wednesday September 8, five Working Days after month end. All progress and forecast figures below are illustrative.

Part 1 and 2: integrity and progress

The data date is right and the settings match UP05: Retained Logic, total float computed as the smallest of start and finish float. One activity, "Roof insulation and membrane", shows an actual start of Monday August 23, which the owner's representative confirms against Halvorsen's daily reports and the Consultant's field review. One problem: "Install roof-top unit curbs" has an actual finish of Thursday September 2, after the data date. That is an invalid date, and it goes back to Halvorsen to correct.

Progress also has to agree with money. The August payment application claims joists and deck as complete, and the schedule shows the deck finished on Friday August 27, so they agree. If they did not, the owner would raise it with Halvorsen and with Ridgeline Architects Inc. (fictional), the Consultant who certifies payment.

Part 3: logic and critical path

View the data

Activity	Baseline start	Baseline finish	Update start	Update finish
Erect joists and deck	Mon Jul 12	Fri Aug 13	Mon Jul 12 (actual)	Fri Aug 27 (actual)
Roof insulation and membrane	Mon Aug 9	Fri Sep 3	Mon Aug 23 (actual)	Fri Sep 17 (forecast)
Dock door framing	Mon Aug 16	Fri Sep 3	Mon Aug 16 (actual)	Fri Sep 10 (forecast)
M6 roof complete, weathertight		Fri Sep 3		Fri Sep 17 (forecast)

All dates 2027, illustrative. Data date Tue Aug 31, 2027.

Figure 2 shows what moved. Joist and deck erection ran two weeks long because of a late deck delivery from Halvorsen's supplier, and the roof membrane slid with it. M6 is now forecast for Friday September 17, nine working days after its baseline of Friday September 3 (Labour Day, Monday September 6, is a non-working day). Dock door framing started on August 16, while the deck was still going up; that is out-of-sequence progress, and under Retained Logic its remaining work waits for the deck, which is correct.

The comparison against UP05 shows two quiet changes. Halvorsen shortened "Interior slab sealer" from 10 to 6 days, and deleted the finish-to-start link from "Roof membrane" to "Warehouse lighting rough-in", replacing it with a start-to-start link with 10 days of lag. Both pull work earlier, and neither appears in the narrative.

Part 4: narrative and float trend

View the data

Update	Progress month	Total float to M9 (working days)
UP01	Mar 2027	15
UP02	Apr 2027	14
UP03	May 2027	12
UP04	Jun 2027	12
UP05	Jul 2027	9
UP06	Aug 2027	4

The narrative says M9, Ready-for-Takeover and Substantial Performance, is "on track for January 14, 2028". That is true of the date, and Figure 3 shows why it is not the whole story. Float on the path to M9 has fallen from 15 working days in UP01 to 4 in UP06, and the two logic changes above are what kept the date from moving. Without them, the longest path would run through roof membrane and lighting rough-in, and M9 would sit at or near zero float.

The narrative also mentions "rain days in August", but Halvorsen has given no Notice in Writing of delay under GC 6.5.4, which is due to the Consultant within 10 Working Days after a delay starts. The owner does not argue entitlement in a schedule review; it records that no notice has been received.

The owner's response

The owner's scheduler returns UP06 as "revise and resubmit" with four comments: correct the invalid actual finish; support or restore the slab sealer duration and lighting logic; compare critical and near-critical paths with UP05; and give a recovery plan that protects the remaining float to M9. The item goes on the agenda of the next OAC meeting, as in lesson 11, and the float trend goes into the owner's monthly report (lesson 12).

Owner's move

• Write the update rules into the contract. Native files, a fixed cut-off, a narrative with specified content and a deadline belong in the Supplementary Conditions and Division 01, not in a kickoff slide.
• Check integrity before you read dates. A wrong data date or changed calendar makes every forecast unreliable.
• Compare with last month, not only the baseline. Logic and duration changes hide in the month-to-month difference.
• Chart float, not just the finish date. Ask for recovery while float is still positive.
• Reply in writing every month. A dated response of accepted, accepted with comments, or revise and resubmit is the record you will need if the job ends in a claim.

Common mistakes

1. Reading only the finish date. A steady finish can hide float loss and logic changes that make it unreachable.
2. Accepting updates by silence. If the owner never comments, the contractor can say every revision was accepted.
3. Ignoring the link to payment. Schedule progress and certified progress should describe the same work.
4. Treating a narrative as a delay notice. "Rain days" in a narrative is not a Notice in Writing under GC 6.5.4.

Quick quiz

1. An update has a data date of August 31. Which of these is an invalid date?

   1. An actual start of August 23
   2. A forecast finish of September 17
   3. An actual finish of September 2
   4. A forecast start of October 4

2. Under CCDC 2-2020 GC 3.4, how often must the contractor update the schedule unless the Contract Documents say otherwise?

   1. Weekly
   2. Monthly
   3. Quarterly
   4. Only when the Contract Time changes

3. What does Retained Logic do with an activity that started out of sequence?

   1. Ignores its predecessors for the rest of the work
   2. Makes its remaining work wait for its predecessors to finish
   3. Deletes the predecessor link
   4. Sets a hard constraint on the activity

4. The finish date has not moved for three months but float to M9 has fallen from 15 to 4 days. What should the owner do first?

   1. Nothing, because the date holds
   2. Issue a Change Directive
   3. Find what changed in logic and durations, and ask for a recovery plan
   4. Rebaseline the schedule

5. Which step should come first in the monthly check?

   1. Reading the narrative
   2. Checking the data date, calendars and settings
   3. Reviewing the critical path
   4. Charting the float trend

Show answers and explanations

1. C. No actual date can fall after the data date. Forecast dates after it are normal.
2. B. GC 3.4 requires monitoring and monthly updating unless the Contract Documents set another interval.
3. B. Retained Logic keeps the original dependency for the remaining duration; Progress Override is the option that ignores it.
4. C. Float erosion is the early warning. The owner finds the cause and asks for recovery while float is still positive.
5. B. Integrity comes first. A wrong data date or changed setting makes every later step unreliable.

Key terms

Schedule update

A copy of the current schedule with progress recorded to a cut-off date and remaining work rescheduled from the data date.

Data date

The date that separates actual progress from forecast; called the status date in Microsoft Project.

Out-of-sequence progress

Work that starts or finishes before the logic says it can.

Retained Logic

A scheduling option that makes the remaining work of an out-of-sequence activity wait for its predecessors.

Progress Override

A scheduling option that ignores the logic for an out-of-sequence activity's remaining work.

Float erosion

The loss of total float on a path over successive updates.

Recovery schedule

A revised plan from the contractor showing how lost time will be made up.

References

1. U.S. Government Accountability Office, GAO Schedule Assessment Guide: Best Practices for Project Schedules, GAO-16-89G (December 2015).
2. GAO, Best Practice 9: Updating the schedule using logic and progress (online edition of the guide).
3. GAO, Best practices checklist: updating the schedule using actual progress and logic.
4. Oracle, Settings tab of the Schedule dialog box, Primavera P6 EPPM Help, Version 26.
5. Deltek, DCMA 14-Point Assessment metric descriptions, Acumen 8.11 help.
6. Canadian Construction Documents Committee, CCDC 2-2020 Stipulated Price Contract, GC 3.4, GC 5.2 and GC 6.5. Clause numbers checked against a publicly posted tender copy; buy the form from CCDC.
7. Singleton Urquhart Reynolds Vogel LLP, Proving delay and damages: lessons on critical path analysis in Dependable Mechanical v Ledcor (January 2026).

Verified on November 6, 2026.

Next lesson in this trackCost reports, forecasts, contingency