This is going off topic again but:
There is no mix and match between any paterson and Jobo tanks, unfortunately. That would have been a cool thing, but just does not work, in any direction.
2520 tanks "only" need 1.25l, not 1.5l. Jobo make a 2L bottle, and other makes of shrink bottles that hold more then 1L are out there and plenty cheap.
If you like your dev process, there is no need to change it, just mix 1.25L of dev and do you think as you would have with any other tank. The Jobo 2509n has no risk of sheets being scratched, or become dislodged or anything else for that matter.
Then stop/fix with tiny amounts of chemistry (300-500ml) while rotating, or use 1.25L for inversion.
The Jobo 2500 tank system for sheet film processinf is a time and result proven system that works for many folks around the globe, most of whom do not have a Jobo processor.