The Now boxsets do not always mirror the Sky boxsets unfortunately (Motive and Carter that is shown on the sky boxsets list has not come to Now tv (perhaps due to them being shown on sky channels not on Now Tv (e.g Alibi and Universal Channel)).
Hopefully we will see the Sky boxsets on Now TV that you mentioned (also The Newsroom and John Adams which is due to Sky boxsets on the 27th December). Now TV used to do a blog of what was on in the month ahead but that was stopped some time ago (would be useful if they could bring it back)
Those three TV shows that i mentioned are HBO productions so i would expect them to be available on Sky Atlantic Boxsets (though this hasn't been confirmed by NowTV yet).
I know Game of Thrones is returning on Boxsets from the 24th of January 2020.
Agree that the NowTV Blog was quite useful for TV shows & Movies coming during the Month on NowTV.
I tend to use Vodzilla website for dates regarding TV shows and movies coming during the month nowadays.