Feel that every time I check my email. My brain just turns a few seconds into a whole drama.

No way! I always figured it was just about age, but that makes so much sense. The pressure thing really explains why old leather has that unique feel. I guess I never considered how the making process itself could change the material over time.

Pruning the infected branches like @noah387 did is spot on, but bagging them right away is crucial. Copper fungicide in spring works wonders if you keep up with it every few weeks.