[oscillon]

And on the ticker - I don’t want to be a continuous tracker so I only talk about it when there’s a potential major change - now it works during London-produced NC hours, including generic newscasts and UK opt-outs, between 0700 and 2300. BBC1 bulletins and Newsnight simulcasts, Washington and Singapore hours don’t use it. This new format is in effect after all London-produced NC newscasts moving to C.

This appears to be the pattern indeed, good spot! However, I'm not sure you can link it to the NC move to Studio C, which happened on April 24.
Working ticker was not seen much until May, and even during the last week London-produced daytime hours sometimes had a static ticker (e.g. May 2nd: 5pm hour, The Context)

UPD. Well, right now, May 9th, 1400 UKT hour, the ticker is again static on the UK feed for some reason despite it being a London-produced NC hour with no UK opt-outs.