The time window

stored time ≤ block time < deadline. Both edges are the contract’s, not a person’s accept button.

The edges

01
The unit test is one_nanosecond_before_the_deadline_clears_and_the_deadline_does_not. Before the stored time the code is ERR_NOT_YET.
02
Accept is not a method. The stored time does not prove the field report was done.