I took a photo of the sign which is a bit more nuanced than just “exciting plans”.
Notably, the presence of the BA Logo, the implication that BA are working on the development plans, and that BA expects us to be excited about them
(why would BA find an expansion to Aspire exciting?).
It also states that the Aspire lounge is available “in the meantime”, which implies that the Aspire lounge (expanded or not) is not the final product for BA pax.
Maybe plans have changed since this sign — but as it’s the only info we have and has been referred to multiple times, I thought it worth highlighting the exact contents.