Your first port of call should be to contact BA to see if you can change your flight booking to include the MIA to TPA leg and what costs will be involved.

BA do of course fly direct to TPA but from Gatwick - you might of course need to pay change fees and fare difference costs if you change your current booking.

If that's not an option and you book a seperate MIA - TPA flight with AA you might be able to get the bags tagged to TPA as BA/AA have an interline agreement but the greater risk in my view is missing the MIA - TPA flight.

Whilst 4 hrs would normally be ok for an international to domestic connection there is a chance that the schedule for your LHR to MIA flight could change before July 2013 which could significantly reduce the connection window - if you were to miss the MIA - TPA flight for any reason you'd simply be classed as a no show as it's an unprotected seperately ticketed flight.

Thanks for the replies folks - should've said, the Clubworld seats were booked using Avios....so couldnt get direct to Tampa on outbound and to change booking now would I presume be no guarantee of securing what I presently have !!

My destination is Bradenton - around a 45 minute drive from TPA and although as of now, all I have is a confirmed hire car rental ( £50 deposit paid ) picking up at MIA and possibly , as was my first thoughts, driving the 200-odd miles - I'm inclined towards flying and then changing my car rental booking ( with Alamo and not Avis / BA ) to a TPA pick up. Do you think it advisable to wait until next Spring / early summer before committing to the AA flight ? For reference, its only £60 or so each to fly AA from MIA to TPA if I book now.....?

Taking everything into account I think I'd go with the car rental option and drive from MIA to Bradenton - there is no risk with this option.

Buying a MIA - TPA flight now might be cheap but it's unprotected so you could lose out in the event of a schedule change.

Buying a MIA - TPA flight later might resolve the schedule change issue but is likely to be more expensive.

Although you are looking at a 4 hr drive this is offset by the time waiting in MIA to catch the TPA flight.

Car rental is more secure and less stressful in my view - I've driven that route from MIA before and it's straightforward.

Tom - very many thanks for your assistance....it was indeed my first choice.....I'm not overly phased with the drive - we drive thousands of miles each year in the U.S......I'd rather just get on with it if I'm honest !!