An awful lot can happen in a month! I would imagine you are drawing all foundation too. Sometimes bees do not like to move up into another box. I hate to tell you to stack three boxes on as it would give them a large area to control. I guess the way I would do it if I had to was to put the two empty boxes on the bottom board and put the box they are working in on the top. That way the bees can hopefully maintain a bubble of warm air at the top, which they couldn't with empty boxes on top.
I would leave no more than an inch of entrance for them so they don't get robbed out. I really hope that the flow continues and they don't starve out. A month is a long time to abandon a package pulling foundation. I might put a wet newspaper on the topbars and pour on ten pounds of granulated sugar as an insurance policy.
I would leave no more than an inch of entrance for them so they don't get robbed out. I really hope that the flow continues and they don't starve out. A month is a long time to abandon a package pulling foundation. I might put a wet newspaper on the topbars and pour on ten pounds of granulated sugar as an insurance policy.