OPS.10.2:5.1 - A deliverable with a join and shared deadline margin

A report needs preparation P, taking four hours, and evidence extraction E, taking two. Different people can perform them concurrently from time zero. Review V takes three hours after both finish; release R takes one hour after review. These resources are independently available, durations are known, and release completes delivery. The deadline is hour ten.

The precedence path P-V-R takes eight hours and controls earliest delivery. E has two hours of free float before its delay moves V’s early start. Starting E at hour two preserves delivery at eight and may avoid producing an input earlier than useful. Starting it at four instead gives V at 6-9 and R at 9-10, consuming all final margin.

P, V and R each have two hours of total float against ten, but they share those hours. Delaying P by two moves V to six and R to nine; another two-hour delay of V would miss the deadline.

To preserve one hour before the external deadline, use an internal delivery target of nine. The latest starts become P at one, E at three, V at five and R at eight. They jointly give one feasible deferred plan with the intended final reserve.

Return to execution of the earliest-start plan. At hour two, preparation is found to need three further hours instead of two. E is already complete. Continue P to five, then V at 5-8 and R at 8-9. The new final margin is one hour. The changed input reopens preparation and its successors; E’s completed result remains available.