Also, if I put in for a GS and am willing to accept a trip less than 12 hours while on long call, is the trip a proffer or am I bound to take it?

Reason I ask is that most times during the day I could make checkin much less than 12 hours, but for a few hours in the evening, I'd need the full 12 to make it. I thought about limiting the hours they could call me, and the time to report via the preference qualifiers, but this could unnecessarily limit a GS if it came up mid-morning.

Anyone have any firsthand experience with this?