Well I mean there seem to have been various suggestions floating around from people supposidly close to things, which suggested both bids would be based on new stock with MK5's being used by taking them off the Redcar route, with presumably 2x185 taking over that route, the bid for Northern would presumably be based on additional 195's, although I suppose its conceivable that Northern could have produced a bid based on the spare 185's I dont think Northern's bid will be based 158's as it offers no improvement to what already exists.
The only bid that seems to really make sense to me is the TPE bid, and if they opted to use 2x185 instead of Loco Hauled given the low relative seating of 185's given the 1st class provision I think its very unlikely that would provisioned to run single 185 they would have to be pairs.
Of course the Northern bid could be lower, although would it be even valid now its changed to OLR. Covid of course could well change things, and do the Dft think it should be more of an Intercity style operation (Tpe) or a Northern Connect style operation.