OPS.10.2:5.4 - A calendar gap makes final margin unusable for a test

A maintenance test becomes ready at hour two. It needs a rig and an engineer together for three uninterrupted hours. A separate analyst then needs one hour to issue the acceptance result and is available throughout. The rig is available from two to ten; the engineer from zero to five and from six to ten. Acceptance is due at eight.

The test fits at 2-5 and acceptance work at 5-6. The final margin is two hours, but the test cannot be postponed by one hour: 3-6 crosses the engineer’s absence. The next complete test window starts at six, giving acceptance at ten. Within the original deadline, the margin can postpone the analyst’s work, not the test.

Before execution, the engineer’s first window is shortened to end at four. Common availability before the latest possible test finish at seven is 2-4 and 6-7: three hours in total, but no continuous three-hour interval. This excludes acceptance by eight. The earliest remaining test is 6-9 followed by acceptance at 9-10.

The obstruction identifies a useful remedy to investigate: restore attendance through five or obtain another qualified continuous window ending by seven. Merely reporting three available engineer-hours, or silently allowing the test to pause, does not answer the stated operation.

These examples are constructed scheduling cases. Their conclusions follow from the stated intervals and bounds, not from measured industrial performance.