Data date

What the data date controls

When the scheduler advances the data date and records progress, the software re-plans all remaining work forward of that line. The forecast finish, the float values, the critical path — all are computed as of the data date. An update is really a statement: "as of this date, here is what happened and here is what the logic now implies."

The failure modes to catch

Three checks catch most abuse. First, staleness: an update with a data date weeks older than its submission date is reporting old news as current. Second, progress on the wrong side of the line: activities showing actual dates after the data date, or planned work still sitting before it, mean the update was not statused honestly. Third, a data date that does not match the agreed reporting cutoff makes period-over-period comparison quietly wrong.

None of these require judgment calls — they are mechanical, and they are exactly the kind of check that should run on every submission before anyone reads the narrative.