Freightliner don't have many spare locos sitting around post coal drop off, as mentioned the Russell's traffic ex Daventry is now with FL, 4x90's a day on hire to GB to cover their 92 woes, these backfilled with HH locos on intermodal jobs, new traffic won out of Tunstead, and heavy requirement for Network Rail infra work, generally 40-50 on a weekend and 20 or so midweek, don't forget FL haul all the HOBC / MOBC kits but as they only usually run overnight you don't see them much.