Looks like Hotswap is back, after our host finally figured out that rebooting the server or trying to reinstall it isn't going to solve a problem when the IP of the server is null routed.
I'm not happy with this entire support fiasco, so whilst Hotswap is up for now - I'm currently looking into alternative options. We no longer need as many game servers as we did before, and players can host their own for the server types which aren't as popular.
Yesterday we also experienced some unexpected problems with the German server, resulting in forum downtime and pretty much everything else which we host disappearing. Restarting all game servers has now fixed this.
Looks like this is the server week from hell for me, hopefully things can now get better from today!