Site Sync no longer works after 8.0 to 9.2 upgrade

Has anyone ran into the issue of Site Sync breaking after upgrading to Sitefinity 9?

We setup 2 test sites and 2 test databases to test the upgrade and everything was looking good until we tried syncing content.  If we publish a page on server A the Site Sync list correctly shows that 1 page is available to sync, however when we go to the screen where you can select individual pages to sync the page just shows an infinate green progress bar on the top and nothing every loads.

Similarly when clicking the 'Test connection (s)' button to validate the connection between the 2 servers we just get an infinite progress bar on that too and no exception is ever thrown (we already have other Sitefinity 8.0 test instances on these boxes which sync fine).

There are no errors thrown on the server or in the SF logs unfortunately.

After some further tinkering I made the direct web api call for the 'Test connection (s)' button and was able to get the exception (the error was being gobbled up somehow when just using the button on the sync page).

Turns out I didn't patch the SVC file found here \Sitefinity\Services\SiteSync.  After patching that all was well.

Thanks,

Damian