I have 2 hives. Yesterday early morning when it was still a bit brisk out, hive 2 had some bearding on it. Popped the lid to peek thru my screened inner board and you could barely see any of the tops of the frames - meaning, no space between bees hardly at all - on tops of the frame. Couldn't see anything down between frames. I had to be at work shortly, so I threw on another medium with all new frames. My thoughts were they've run out space. My other hive (#1) had an extra medium on it from last year, with honey and empty frames alternated. So I know that hive had room to expand, they were not exhibiting this behavior, and there was still some room visible in it.
I will be able to inspect tomorrow to tell more, but ITMT does this seem "pre-swarm-ish"? Did I make a good decision to expand? When I open tomorrow, should I alternate empty frames with honey, and is now a good time to reverse? Running in the 70s and 80s all week with lows from 40s to 60s. Unusually warm for this period. THANKS!