I was just combing through
DigitalBitRate website and saw some BT Sports Channel stuff that seems new.
First the non-new, C073/Tsid22 has BT Sport 4K UHD, this is the current 4K channel, I'm mentioning this location on the page as this is the existing service.
What I'm drawing your attention to is this...
C052/Tsid14 has BTSport 4K Hidden, BT Sport 4K Slate and BT Sport HD Hidden.
Something new from BT?
It's possible they are preparing to move services, but why labelled as they are?
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I just looked at the screen shots that accompany them. The HD Hidden has a BTSport 2 logo, the 4K Hidden shows what looks like an advert for a tablet, and the Slate shows BBC2 HD move (!). Weird, but maybe just tests.