These two versions should be compatible, so I think that something else happened with Server here.
Might worth a check:
1. Port numbers - are all of the installed components have a different port number? If no, make sure all of them have a different number.
2. BIMcloud only features - do you have any BIMcloud only feature turned on? Full Backup or External Storage for Snapshots. If yes, please turn them off.
If none of these help, I suggest you to contact your local support on Monday. They will need your BIMcloud logs. Please collect everything what is mentioned here: https://helpcenter.graphisoft.com/knowledgebase/43351/
About the deadline: I don't recommend to do this - when you uninstall BIMcloud Server, it deletes all connecting data, including projects and libraries. There are possible ways to get out of it, but I do not recommend to do this without a technical support engineer or developer from GRAPHISOFT HQ.
Instead, I suggest you to install another BIMcloud Basic, locked to Archicad 22, and restore here the most important projects from Snapshots.
1. Check in your current BIMcloud Manager that what is the ID of your projects, which you need to finish your deadlines.
When you select a project from the Project root, in the URL you will see something like this:
Project ID will be those characters I highlighted bold.
2. Once you have the ID, go to your Projects folder in Windows File Explorer (If you are not sure where it is, you can start the BIMcloud Server Configurator to get the proper path.) and navigate to the folder with the same name as the ID you got in the first step.
3. Inside this folder you will find another folder, called Archive.
4. Here you will find all of your existing Snapshots. Copy the latest one.
5. Install new BIMcloud Basic, lock it for Archicad 22.
6. Rename the .archive from step 4. to .BIMProject22.
7. Import to the temporary BIMcloud Basic.
If you believe that your Snapshot would miss too many info, then I suggest to open the project from Archicad (you should be able to access it offline if you didn't leave it) and save it as a .pln. When it is done, you can re-share it to your temporary BIMcloud.
I hope this way you can manage your deadline.
Customer Engagement Expert, Community Admin