Avocado ripe near surface, very not near core
 

I discovered avocados this year, and have enjoyed the immensely. Learned how to ripen them in paper bags over the course of days. Been working out well until recently. Recently, my avocado's have been been appearing to become reasonably ripe in terms of surface tenderness, but when I cut them in half and try to twist them off the core, they refuse to cooperate. With enough insistence, it's not the avocado halves that twist off, but the skin itself. Since the surface is ripe, it also becomes a bit of a mushy, messy affair. I end up cutting the flayed avocado into quarters and trying to wrestle the sections off of the core. At the core they're stuck on as if crazy-glued. In fact, even as the quarters come off they take the surface of the core with them. It's another flaying exercise to get the "skin" of the core off the (no mutilated) avacado quarters. And the meat near the core is quite stiff, like a ripe but uncooked potato.

What would cause such a change in ripening behaviour? How can one get back the uniform ripening?

Avocado ripe near surface, very not near core
 

Avocado ripe near surface, very not near core
 

songbird wrote: is this fruit off the same plant?

I'm pretty sure not. It's from a grocery outlet. But in my metropolitan neck of the woods, avocados are Haas by default. I will double check. Thanks.