We essentially had that capability in the 70's but then scrapped it. Black arrow aka the "lipstick" rocket.
https://www.rs-online.com/designspark/rockets-return-the-uk-space-launch-industry-then-and-now
Feb 2015 shows the pile driver boat docked in the corner of Bay 2 as well. Looking at the LBP pic for anything that could potentially be crane related, I suppose this collection of pixels could potentially be a crane/dredger. Tbh it could just be a boat with a mast.
Back in the days of the London pics, I was thinking I wish these were higher res … not anymore.
>something else under the surface with its bow pushing waves ahead?
Certainly looks that way. (I've come up with and posted crazier theories.)
Just going with the crazy theories (which tbh I am avoiding).. flipping the hotel (mirror) gives us a 25 (5x5)