Checked a couple of nucs I'd made up with late season queens a few weeks back and left alone for a few weeks so the queens could settle... Took a gamble on some discounted Carniolans from Bee-who-shall-not-be-named.
Turns out that the two tabs on the introduction cages were different to any design I've encountered before. One of the tabs leads to a queen excluder sized gap meaning that if it's hidden in fondant and the beekeeper only opens one tab, the queen can't get out. One was alive and I let her join the nuc but suspect they won't make it now as they've lost a week or two of laying time. The other the queen had died. Bit gutted but will chalk that to experience.
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