I'm pretty worried about major winterkill this year with the lack of dormancy (to be fair, I do tend to be a foreseer of doom when it comes to winter damage). I've seen early freezes that left the trees with leaves on them before, but a warm spell in November always allowed the trees to finish going dormant and the leaves to drop. Not this year, plus that nasty cold spell in December could be really hard on trees that didn't properly harden.

My September Ruby apple must have at least 60% of the leaves remaining. In the over 20 years it's been growing it never had any leaves at all on it this late into winter. I'm particularly worried about the cherries since I've seen bad winterkill on them in some other winters but they've never had leaves on them into the winter like they do this year. The plums and saskatoons and pear should be fine as they dropped all their leaves before the freeze.

Sure, one can expect winter/freeze back, in severe cases the entire tree can be wiped out,...happened to me before.

>>Will the grafting be affected? Not so much the grafting has anything to do, ..it's the cultivar itself, in terms of hardiness,..example, a zone 5 plum can have much more damage then a zone 3 plum in our climate.

A young tree or rootstock with much vigor and a new graft can wipe out the whole graft, ...but doing much better when top grafted on a older tree/branch which has less vigor.
The hardening off is also better in a top grafted/older tree.

Many of my plums and apples have leaves on, some might die back. Sept. Ruby apples are very hardy and most can take it.
Leaves froze green on the tree in October from the cold snap and are brown. Mostly Deer now are nibbling off the leaves.

This cold snap has not let up and I don't remember being this cold for sooo...long. We're almost 3 month in it and never has it gone above freezing temp. since.

This is also detrimental to honey bees, I can expect a great number of winter kill in this part of Alberta. That includes my hives,,..not so much action I see in my 5 hives.