In article , Mitty
wrote:

OK, just to distract you guys from "IFR with a VFR GPS" ---

Flying into Grand Marais MN last week (KCKC) I was out maybe
30 miles at 7000 and got "Cleared for the approach, maintain
4000 until established. Contact advisory ... "

As worded, you were required to vacate 7000. No need to rush down, but you
can't just hang out at 7000 for another 30 miles either.

"Center, that 4000 was pilot's discretion, right?" and got a "Right."

Did I need to ask?

Yup, you did. You did the right thing by asking.

Should I have assumed pilot's discretion? She did not tell me to
descend, just gave me the altitude limit.

If you're at 7000 and you're told you maintain 4000, descending is pretty
much the only way to comply. She didn't give you an "altitude limit", she
have you an "altitude". If she had said, "maintain at or above 4000 until
established", then you could have stayed at 7000 as long as you wanted.
Same with "descend at pilot's discretion and maintain 4000". Or, "Cruise
7000".