Personally, I don't see what the problem is.
It is very common, at many airports, to be cleared beacon outbound maintaining an altitude, and to be cleared for a descent later on the procedure. The usual reason is to maintain vertical seperation from an inbound aircraft, with descent being given only when you are laterally clear of the inbound aircraft.
Bearing this in mind, it is quite understandable that a pilot (student pilot or any other) who is used to being asked to maintain an altitude might, occassionaly, when he unexpectdely gets cleared for the procedure, want to ask for additional clarification.
I always teach my students that if there's any doubt at all about a clearance, the only thing to do is ask. And it's my experience, as a pilot and an instructor, that the need to ask for additional clarification arises more frequently when the clearance is different to what was expected or what has been received in the past.
I'd far rather ask, and see my students ask, than descend without being certain that was what I was cleared to do. Wouldn't you?
FFF
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