Yeah, as others have pointed out at the GB and Bleeding Cool forums, it's hard to believe that BBC Worldwide, which still hasn't released or even announced "The Underwater Menace" 2 despite its being recovered in 2011, wants to rush the release of these alleged new discoveries.
I suppose the difference would be a complete story - after restoration and extras - is ready to go.
Half a story isn't. We still haven't had any confirmation the other half of Underwater Menace has been animated. If Moonbase was comissioned with Tenth Planet, before the Underwater Menace recovery and these rumours started to look promising, its possible they might have waited to see how it panned out before agreeing to any more.
That does seem the most likely explanation for why Underwater Menace is being held back. Moonbase could have been on a pre-prepped long term possibilities list back in 2011, whereas nobody would have been considering UM for animation before part two turned up.
That's prompted me to do back of the envelope work out of what's most and least likely to get the animation treatment. The sums are based on 2 points for each episode that needs to be animated and 1 point for each episode that's missing telesnaps, with the lowest scoring stories being most likely to be animated.
That probably over-estimates the impact of there being telesnaps around has on a story's chances (and if there's no telesnaps or episodes at all, then it might make the animators jobs easier, as they don't have to spend time matching the existing material), but hey, the list comes out as something sensible, so I'll go with it...
So anyway, here's what I came up with:
4 points: Underwater Menace and Crusade - 2 episodes to do (which is the limit BBC DVD currently say they can afford), plus telesnaps.
8 points: Wheel in Space and Faceless Ones - as above, except four episodes to do, which is twice as much.
8 points: Savages, Smugglers, Highlanders, Macra Terror - also four episodes with telesnaps for all, but no surviving episodes, so probably less likely.
9 points: Galaxy 4 & Celestial Toymaker - only three episodes to do, but no telesnaps for reference. If you ignore the telesnap issue, then these become the most likely candidates apart from Crusade and Menace.
10 points: Abominable Snowmen & Web of Fear - five episodes to do, from telesnaps.
11 points: Enemy of the World - also five missing episode, but there's no telesnaps for part four (why couldn't John Cura have taken the previous week off, eh?).
12 points: Evil of the Daleks - six episodes to do, telesnaps for all of them, plus one episode already in existence. (Question - if it was done, should the animators be faithful and have the Daleks' domes change shape from studio to model work in part seven?)
12 points: Myth Makers and Massacre - only four episodes to do, but no telesnaps for reference.
12 points: Power of the Daleks & Fury from the Deep - six episodes to do from telesnaps, but no complete ones to include.
15 points: Marco Polo - 7 episodes to do, and no telesnaps for one of them.
15 points: Space Pirates - only five episodes to do, but no telesnaps, no reference shots for several major characters, and the main villain doesn't even appear in the surviving episode to give you reference on him!
30 points: The Dalek Masterplan (with Mission to the Unknown) - nightmare! 10 episodes to do, no proper telesnaps, few or no reference shots for several major settings and characters... Will only be done if a fan wins the lottery and pays for the work!