>I treated the colony with Apistan in the spring and have the varroa under
"control".

Are you sure?  Apistan is worthless as a varroa control in our area.
My friends in Georgia say Apistan has little effect on varroa in fact mite
counts increased during the treatment period.

What you describe is the classic signs of bees which have been munched on by
varroa and then emerged.

 Its possible that the fall formic treatment solved the problem if the
varroa load was below a level a treatment would work.

Test!

Bob

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