Mark Hopwood in yesterdays Green Signals interview (available on You tube) alluded to being stored outside, doing their sensitive electronics no good.
Although he did not directly say condensation, frost, damp, mildew etc had damaged them, he used an analogy of if you were going away for a year you wouldn't store your laptop with its electronics on your garden shed roof, then expect it work.
Reading between the lines, was clearly saying if Leasing Co wants to store trains, got to do lot better to protect them against weather, and electronics need protecting with those moisture absorbers (desiccant or silica gel pouches) so everything stays dry. 25 year old electronics do not work reliably after getting damp. I got the impression now regretting having to reactivate trains (175s) that had been stored long time unprotected as just a heap of trouble, and meanwhile leisure traffic has grown and they are struggling with capacity.