Okay, how would we feel about an 11 a.m. (BA1477) arrival at LHR with everything else the same?

I was hoping the 12:25 would work because I could get it with miles, but the 11 a.m. isn't too expensive.

The sleeper isn't an option because it leaves too early, we are arriving in GLA that night around 10:30 to the airport. I have learned an important lesson booking this trip -- do not book the internal flights first before getting the big international flights!