You asked this question one day too early!
We just found out that the old servers are physically coming out tomorrow. This is more than a little surprising because we had been told this would happen next week. We had a plan for the move to the cloud, and even a backup plan in case that one didn't work, but that's all been thrown out the window now.
A few minutes ago we shut down prpnet.primegrid.com so we can safeguard the data. Therefore, the following ports are down, and will stay down until we can bring them up on a different server:
GCW, Primorial, Factorial, GFN32768, GFN65536, 27, and 121.
Ports on other servers are not affected.
We're really sorry for the short notice and any inconvenience this may cause.
I'll post more details when they become available.
P.S. I know the biggest question you probably want us to answer is "How long will they be down?" Of course, I don't know, but if I had to guess, I'd say 3 to 4 days. It may only be hours, it might be a week or more, but 3 or 4 days seems reasonable considering everything that's going on (the Valentines Day challenge, availability of personnel, etc.)
My lucky number is 75898524288+1