I don't know if this is a feature, or if it is a bug, or if even it has been discussed before, but sometimes when I get my crossing restriction I could be told to "expect a clearance to cross 40 miles from xxx at 12,000 ft." I will then plan my continued decent so that I will make that restriction. When I get my final restriction at the 70 mi. from destination/last VOR in the flight plan, I would sometimes be told to descend to 11,000 ft, which is not what I was originally told to expect.I really have to listen because the change sometimes catches me by surprise, with no acknowledgment that the restriction had changed. The first few times it happened, I was approaching the crossing point, at 12,000, and told to turn to a heading 90 deg to the left or right, which of course signified that I had missed the restriction, but since I was at what I had been expected to be at from that first notification, I didn't understand, I just figured I should drop 1,000 ft to make RC happy so I could continue the approach. Upon listening more closely in subsequent flights to a possible change in my crossing restriction at that 70 mi. point, I have been able to hear that I had sometimes been given a different altitude than the first notification.So, is this a feature, a bug, or something else?Rod S.

feature. difference between a "new crossing restriction" and "old crossing restriction"i'm sure it is covered in the manual. every tutorial has something to learn about, regarding crossing restrictions.depending if there is a vor within 5 miles of your arrival airport, will decide on which crossing restriction you getjd

In addition to what jd said, also remember that ATC is a very dynamic environment - traffic changes, wx changes, runways change, speeds change, altitudes change, headings change, and even airspace changes sometimes.When the controller tells you to "expect" something, that's just it - "Expect". But that can change for a variety of reasons. "Expect" is not a clearance!In fact, I heard a controller say one day that a sign of good controlling is that you must be able to change your mind, if you think your original traffic flow plan doesn't seem to be coming together as expected. Controllers are always working their brains to come up with backup plans, just incase his/her original plan fails.As a pilot, you just have to keep your ears wide open :()Subs