Sam Spade wrote:


In Southern California and all other stratus-laden areas of California,
which are in TRACON airspace, the assignment is alway at, or above MVA,
and predicated on recent pilot reports.

It is not possible (at least in these parts) to continue such a
clearance as an IFR, VFR-on top without an IFR flight plan. If there
was an IFR flight plan there would usually not be a clearance to on-top.

Are you saying if, for example I am departing BIL, and without a flight
plan I request a climb to on top, and then when on top I request on-top
to Salt Lake City, you would grant it?


Of course. It would be nicer if you had already filed a flight plan to
SLC because then I can just change the altitude in the computer to OTP,
but I can always quickly enter the flight plan. Our cargo guys here
have prefiled IFR flight plans. Whenever they can they go OTP and they
often tell us they are OTP as they are taxiing out. So we never give
them a hard altitude but simply "maintain VFR OTP". This works because
most days are just like today, not a cloud in the sky.