Ashmead's Kernel ripening

I have an Ashmead’s Kernel apple tree that finally produced some fruit for the first time this year. They seemed to be pretty hard when I picked them even though a few had fallen off the tree in their own.
I have them in the fridge. They still seem pretty darn hard. Even my horses had trouble crunching through one.
How long do you need to keep them in the fridge before they have aged enough to eat?
When do they ripen in your area?
I only have a few so I hate to keep testing one every few weeks. If I do that I will run out of fruit to use.
This is an interesting looking apple and I have read great things about them here on this site.
Thanks for everyone’s help and advice.

They ripen mid/late season for me in z4b Maine, spread over a few weeks from late September-mid October. Eating quality improves in storage and might peak a month or two after picking. Great apple!