Dead colony but three frames of stores. Why?

A friend of mine posted this in another forum BioBees.com. I haven't seen an answer yet & was wondering if the good people of Permies.com would care to weigh in. Together we can all increase our knowledge.

ringtor wrote:Today was warm and sunny so I tapped my TBH but no bees came out. They had been flying three weeks ago.
Opening showed that they were all dead - presumably from starvation.
BUT there were three frames of stores and one feeder with fondant. There were three empty frames between the full ones and the cluster.
Should I have checked them earlier and moved empty frames?
I have hesitated to open the hive because I have a cold garden and they were flying to the Mahonia.
I checked my other TBH and fed with sugar and fondant to be on the safe side and hope they will survive. I haven't lost a hive in 5 years but I am sad about this one.

horizontal hives can be a bit tricky this way. I don't have much experience with them personally, but the consensus I've heard in my locale is that comb manipulations need to happen before the winter cluster forms and ask the honey reserves need to be on one side of the cluster. if there is honey on both sides, the cluster will not be able to cross the gap of empty comb to get from one side to the other so the can starve even with plenty of honey left in the hive.

how to arrange where the cluster forms is not a technique I'm familiar with.

Just to follow though & update this thread here are the replies given so far...

trekmate
Only if the side entrance is in the middle of the side. The brood nests tends to be near the entrance and honey can then be stored either side. End entrance or entrance at the end of a side removes this problem.

ringtor
Thanks for all your replies, it is most helpful. One point I noticed on another thread was that it is a good idea to have a hole at the top of the wax so that bees can pass more easily from comb to comb.
While it may be a cold garden there is no arable land within 3 miles so I think stavation is the probable explanation. They couldn't reach the stores that were left.
I have a microscope and checked for nosema but only found pollen.

biobee
I find that bees routinely leave 'transfer ports' at the top of combs so they can easily travel sideways in winter. I have even designed top bars with such holes built in.

Thanks for the help.