I don't know about these things in detail, but since my office overlooks the viaduct approaching Piccadilly (in Ardwick) I can tell you that EWS and Freightliner run freight through every day - mostly 66's but EWS also run Class 92's on an almost daily basis. On an average day I'll see about 4 Class 66's, two in either direction (usually the same trains) and perhaps a Class 92.
I dunno if that is of any help to you.
