From site's staff on their Facebook page:

Don't panic Mr Mainwaring!

The 522 error is totally normal as the site is down for maintenance. Normal service will resume shortly.

I am off out for the night...unfortunately not to the planned knees up in my local, but for a fish dinner at a friends house (I am allergic) followed by a jam session where all us non musicos will be shushed if we dare to speak....really not my idea of a good end to the decade, but there you go!...

I will resume doing your account resets in the morning (or whenever I wake up)...

For the last time in 2019, do not forget to include your username and your registered email address with your password reset requests!!!!!

See you all on the other side
xx