Yes, there is indeed a change in how we talk to the Team Server. Since Mendix 7.17, where we introduced the new sign-in screen in the Modeler, we communicate through a different HTTP library which causes issues for some users.
For this reason, we have written a troubleshoot guide for version control: https://docs.mendix.com/developerportal/support/troubleshoot-version-control-issues
The time-out issue you are experiencing is also described there: https://docs.mendix.com/developerportal/support/troubleshoot-version-control-issues#2-3-getting-an-error-with-the-message-connection-timed-out
I hope this works for you!
Have you tried it a second time after the error comes up?
URL has changed:
https://docs.mendix.com/howto/collaboration-requirements-management/troubleshoot-version-control-issues#2-4-getting-an-error-with-the-message-project-folder-is-already-locked