Apple tree pruning

I have two large apple trees ( Bramley cookers I think) they are well overdue a prune, I think they would be in excess of 50 years old, and have they become very overgrown. I also have a pear tree as well. The fruit has all but dropped on all the trees but When is the best time to prune these?

November to February, this article will explain more.... [broken link removed]
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