4.19 Remote build for iOS failed connection to remote server

Hi there!

I am getting this error (See image) quite out of the blue after successfully building with this set up for over a week. It has however not been plain sailing and occasionally the build has failed by not being able to reach the remote server.
Right now however, I am unable to build further due to this error during launch and despite several restarts of both machines.
There have been no updates or new installations of anything during this project since successful set up for remote building.
Has anybody else run into this problem? Are there any solutions? All suggestions welcome!

Thanks in advance

I should add that both my Mobile provisions and Developer certificates are all displaying as valid in my projects settings.