I've used top entrances for the last five or six years and will NEVER go back to bottom entries alone. I use a 'notched' inner cover (Thanks Frank!!!! in Canada, this forum misses you)) that can be raised (as supers are added) as my colonies grow (a perfect addition to KYBO IMO).
I'll only open the bottoms as they get big (or HOT) and ONLY if they are a strong colony and then ONLY open the smallest possible bottom entry.
I also use a separate (medium or deep) box above my inner covers as a feed/ventilation box (it has 4 holes on each side drilled and screened over). This and using "ALL Mediums" has been a life changing experience as keeping honeybees goes. 8-) At least for 'this' beek.
That's what WORKS very well for me and mine. :) and is presented as absolutely anecdotal at best as is "ALL" the advise provided on this forum. 8-)
It's all just anecdotal and based on personal experience for the most part.
Thankfully I've only seen ONE SHB which came from a package purchased from Texas.
Wisconsin colonies, regaradless of how they were obtained, and placed in direct sunlight, will not have issues w/ SHB> HOO-RAY!
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