AWI123 is level at 3000 and five miles south of DEPRE when cleared for the
approach. He follows the localizer down and crosses DEPRE at 2141 MSL.

Wasn't there an accident recently caused by a misunderstanding like what
is suggested here? If you are (umpty ump) miles south of the IAF, but
above the initial approach altitude, and get cleared for the approach,
when can you descend? I recall (perhaps imperfectly) that some airliner
descended inappropriately and ran into terrain, while still above the
altitude for the IAF. A clearance for the approach is not (AFAIK) a
clearance to -descend- to the approach altitude from an otherwise
assigned higher one.

If I'm missing something here, what is it?

Jose
--
Get high on gasoline: fly an airplane.
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