They've announced the next season to be released as part of the collection boxset series (before the previous one's even been released) and it's... Season 24:
I will say the trailer's one of the better ones they've done. Some of the others have felt a bit cheap.
The logic behind the release schedule primarily seems to be first and last seasons for each Doctor, although we've had some wild cards like Season 10 (might be because it was Jo/the original Master's last season), Season 14 (Sarah Jane's last season and Leela's first season) and the soon to be released Season 8 (Jo/the original Master's first season), so I guess this fits into that logic, but I'm a bit disappointed because Season 24 is one of the weakest seasons in the show's history.
I pre-order all of these pretty much as soon as they're announced because they sell out quickly, appreciate in value like you wouldn't believe (the last set's already being resold for over double its original price), the special features are usually kino and they come with copies of the original scripts which are like gold dust - even the BBC archive usually only has one copy. So I will be getting this, but I'm not overly excited about having HD versions of such "classics" as
Time and the Rani and
Delta and the Bannermen. I like
Paradise Towers, but I'd say
Dragonfire's the only truly good one on there. But I'd much rather we'd gotten the originally rumoured Season 21. Yes, it has some utter stinkers in it too (
Warriors of the Deep,
The Twin Dilemma), but it also has
The Caves of Androzani and we'd get an upscaled version of *that* scene from
Planet of Fire.
I also think it's a bit cheeky to charge full price for this, considering you get half the episodes you would for a season earlier in the show's history. Even the special features don't make up for the shortfall. Anyway, at least the release schedule seems to have picked up again after going dormant during the original lockdown.