I upgraded to 6.6.3271.50 on the 16th March.
I've now had the same problem when visiting https://ukfree.tv/transmitters/tv/Caradon_Hill/PGSTART500/#pagebar but again not on every visit, in fact, so far, only the first visit!
We will be updating the Forum on Tuesday, 19th of March between 09:00 and 11:00 (UTC) (see the time in your time zone). During this time you may experience some downtime. Thanks in advance for your patience. 🙂