Related to this, they never did find a good term for 1080P, well, other than 1080P.
720P was branded HD, 4K was branded UHD, but 1080P never got a designation like that. This put Sky in an interesting position, as they only recently added 1080P support to their NowTV streaming subscription service, as an optional upgrade to their usual 720P. Having already long promoted their service as delivering HD, [0] they were clearly at a bit of a loss as to how to describe 1080P. They ended up calling it full HD. [1]
Actually, when the HD standards were introduced, 720p/i was officially designated as "HD Ready", and 1080p/i as "Full HD", with the respective acronyms HD and FHD. Ultra HD obviously got the UHD acronym later on.
720P was branded HD, 4K was branded UHD, but 1080P never got a designation like that. This put Sky in an interesting position, as they only recently added 1080P support to their NowTV streaming subscription service, as an optional upgrade to their usual 720P. Having already long promoted their service as delivering HD, [0] they were clearly at a bit of a loss as to how to describe 1080P. They ended up calling it full HD. [1]
[0] https://community.nowtv.com/t5/Sports/HD-or-non-HD/m-p/40699...
[1] https://help.nowtv.com/article/what-is-now-tv-boost