HELP! Hot brake AFTER changing caliper and flexi-hoses

Hi, looking for some advice before admitting complete defeat.

I have a MK1 Skoda Fabia VRS. A few weeks ago, I noticed the OSR brake pads were wearing much quicker compared to the others. The rear caliper, disc and wheel were also getting very hot - even after short-ish journeys under normal braking conditions.

Thinking the caliper must be sticky (although it was only 18 months old), I went ahead and replaced the caliper, discs and pads along with replacing sliding pins and greasing everything but the problem remained.

Fast forward to today: I’ve replaced flexi hoses, tested the handbrake (it’s not that), plugged into VCDS (no faults) and even tried removing the fuse to the ABS pump to see if that makes any difference (assuming it may be pushing too much pressure to the OSR).

I’ve seen similar issues on here but no posts about how or if they’ve been resolved. We had the car for 15 years and she is the best, most reliable vehicle I’ve owned. I don’t want to get rid of her but running out of options.

Any advice will be grateful received.