Getting Navmesh and work better with sublevels to update in 4.19

Hi, I am looking for some info regarding navmesh in 4.19

We are facing a problem where every time a bit of the level changes (we’re using a ton of sublevels for different stuff to allow several people working on it), the persistent level needs to be checked out so the navmesh can be nudged so it’s updated, otherwise it just doesn’t work at all.

We have divided each (linear) map into 3 sections which all have their prop and lighting sublevels, then all three of these maps are put into one big map as sublevels that is then played in the game as a level. The navmesh is in the persistent level of this “bucket” of a map that holds everything in itself.

Any ideas how this could be tackled better?

I have asked the same question in the answerhub some time ago but never received an answer.
From my research there is no way that you can store the navigation data in a sublevel, nor can a navmesh bounding box be in a sublevel. You can place it there, alright and the navigation data builds, but when you have a composite world the nav data simply wont be there when you run the world and after you leave and restart the editor the nav data is gone ans has to be rebuilt.
To me this is very annoying, not so much for the check in check out, but because updates that go to the players in the future and which change the navdata in one sub level will then have to include the nav data of the whole world from the persistent level.
It is a very bad solution that’s implemented here, but I don’t see any way around it. If somebody knows a way to store navdata in a sublevel only, please, share!