Could have been something from BAe Warton, possibly a BAe 125 like this one :
http://www.!!!!!!!!!!!!!!/open.file/561504/M/
They usually route airways though, rather than flying around in the FIR - if you were a bit further North then Rivington it could have been on the Warton ILS I guess.
I was flying back into Barton at about this time and didn't see anything - but I'll ask around for you.