(23 Sep 2022, 8:39 pm)GNE6312 wrote  Was revived at Ashington after 7445 was withdrawn to cover that and now revived to cover 7508

It was never withdrawn from service at Ashington, it simply happened to be VOR waiting parts around the time 7445 (and later 7446 also) suffered major component failure. From memory 1923 was the 7445 replacement.

It then went to Jesmond in early July for engine work, though it's unclear what the intentions were with it. Given it was reinstated quite quickly after 7508s incident, it likely finished it's engine work relatively recently and might have been sitting as reserve for the time being - or they may have had a longer term plan for it (training?).