I'd be very surprised if the Newcastle closure permanently resulted in no lounge. That can be a very well loaded route and will be again when things return to normal.
I wonder if it'll be a case of invitation cards to the Aspire lounge for status passengers, as in places like Munich and Lyon where there is no other Oneworld lounge in their terminal - those two are better than a typical BA outstation lounge - the Munich lounge is way better than the Galleries it replaced!
NCL was very large for its demand though and was a very dated ex-Terraces affair with a few second hand Galleries armchairs. The decor was possibly only one step above the Stuttgart lounge which was so bad they took their name off it and flogged it! (Review in German here)