I think I must have been a bit careless with the last lot of sugar syrup I added.
I added the syrup last Thursday, and over the weekend I found that the bag had split and the contents of a very full zip-loc bag spilled out over the feeder bottom and sadly drowned quite a few bees. I hope no major damage has been done.
Anyway I gave the bees some more 2:1 tonight and I hope things will get back to normal soo. I really need to check to see how much in the way of stores there now is. Perhaps the weather this weekend will be kind.