We are currently in the process of updating TestNet to 1.1.0-pre4.
Servers will be temporarily down during the upgrade process. Upon update, your TestNet client binaries should continue to work (as they are currently verifying with MrSigner so as not to require an update for every consensus deploy).
We are working through some issues with backward compatibility with the newly introduced block version, so there may be another revision coming soon.
Please join us in testing, and as always, let us know if you have any issues.