Version: Both Stable (1.2.0.124) and Exp (1.2.1.127)
Modded: No
Reproduction:

1. Drag in Character_USSR_SR
2. Find the entity labels in the EditableCharacterComponent under Visualization->UI Info.
3. You can see that it has the ROLE_RIFLEMAN role, not ROLE_LEADER.

Even though I didn't see anything in the changelog, 1.2.0.92 appears to have resolved this issue.

In T182663#2635559, @Geez wrote:

Hello TilW.
Are you running any mods? and which version does this occur on?

I looked into this issue, it appears that 1.2 broke the way terrain bounds are calculated.
Meaning when you create a new terrain or resave an existing world entity, the terrain bounds will break.
Reproduction is as simple as it sounds, just create a terrain larger than the default bounds (~3000m) and try to move the camera beyond it.

This appears to be fixed.

Correction, this is only the case for the official worlds, not all read-only worlds - so likely just a part of your publishing process.
While it would still be useful to preserve these layers (both as reference material and for making derivative content), this is not actually a technical issue and can be closed.

Thanks!
Do you know if this will be supported in the future, or not at all?

With "potentially log the specified addonList" I just meant the message printed in GetGame().PlayGameConfig(), a function which calls RequestScenarioChangeTransition().
It's not actually relevant to the problem other than that it confirms I did not just accidentally give it the wrong input. Apart from that, nothing is logged either way.
But here's some detailed info on how to replicate the problem:

Any updates on this?