Why has the order of my photographs in my Bridge Folders changed. How to I revert back to the previous order of over 2000 photographs
It appears that Adobe may have changed their sorting method. I don't have any concrete info on why or whether this is intentional or not.
The mentioned issue is fixed in the latest patch release #184.108.40.2063. Please install and confirm if that fixes the issue.
You can refer to the issues fixed in the patch at the following link https://helpx.adobe.com/bridge/kb/fixed-issues.html