Delta backup failes if previous transfer isnt done.
When a scheduled delta snapshot didnt finish transfer before next instance, it aborts, which means it gets stuck in a never ending loop.
XAPI (XenServer/XCP-ng API) can't have tasks longer than 24h (or 48h, depending on the version). So that's sadly… normal.
Oh, not very good. Any way around this?
No XCP-ng/XenServer workaround, it's a "built-in"/by design limitation (it's considered as "stalled").
So your goal would be to avoid these extremely long tasks (ie: to finish before the task is destroyed)