As announced here: Site Maintenance: 13th Jan 2023
Let me know here if you have any problems this weekend - since weekends are usually when we see the site go down the most.
Thanks for your patience.
Edit:
We're observing that there are regular problems approximately every 12 hours, such as at 9:30AM GMT each day the site is unresponsive. The development team and server admins are aware, fortunately the site comes back up without intervention, but we don't want it to happen at all.
Further edit:
Thanks to the fixes that went in on Friday, we've been able to identify what's contributing to the 12-hour frequency problems - the development team are implementing security measures to prevent it.