V-Flyer

I will be flying into Gatwick from Barbados in First, then going over to Heathrow for my flight up to Manchester. The 2 flights are on separate bookings, so will I be able to use the First facilities at Heathrow whilst waiting for my Manchester flight, ie the Arrivals pre check in for a shower and the lounge post check in?

What ticketing class is your LHR - MAN booked in?

Also, if you are on BA, try here!
http://baflyer.com/forum/

If it's 2 separate bookings, then I would think it not possible sorry as BA don't sell F fares on separately booked domestic routes.

You may be able to use the priority desks, fast-track and the J lounge at LHR, but only if you have BA status or have booked a business fare on the domestic leg though.

My Heathrow to Manchester is just the cheapest ticket available

You'll have access to the LGW arrivals lounge (as you land there) rather then the LHR one (which closes at something like 2.00pm). The BA LGW arrivals is at the Sofitel.

As to getting a lounge on your LHR to MAN am not sure. Having landed in F it might make it possible but having two seperate PNRs probably counts against you.

There is a very comprehensive lounge thread on the BA board on Flyer Talk that includes flight combinations and lounge access like yours.

Surely same day international F travel will provide lounge access at LHR? (Not arrivals though) There are showers in the lounge complex airside at LHR. Separate tickets won't make a difference.

Just an update on my original post. I was allowed in the BA lounge at Manchester on our outward flight to Heathrow without any problems, I just went and asked the BA desk. The friendly girl on the desk said that as long as the 'First' leg of the journey was within 24hrs of the connection I could use 'First' lounges etc. The same applied at Heathrow for the return to Manchester, breakfast of Champagne and bacon butties in The Concorde Room. Great start and finish to the holiday.