Voluntarily by you or is it a change forced by the cruise company?It is a long drive (4.5 hours TPA to the cruise port); you well might not want to drive the whole thing after a transcon flight, but note that your current air itinerary is actually 6:40, not ten hours.To make it quicker and easier the OP should bookmark the Change Itinerary link that is displayed on her MySouthwest Future Itineraries page.I could be wrong but I doubt customer relations can change you to flights for which there is no award availability; it's worth a try, but you should be prepared with a backup plan, such as...this excellent suggestion by tusphotog. Fortunately you are booked on a direct flight to TPA (the suggestion would not work if you already had two flight numbers on your itinerary). Even with your direct flight, if you get a CSR who insists on sticking to the "letter of the law" you won't be able to add TPA-FLL to your itinerary, even though award seats are available on 14-Jun, and you could book it that way yourself online on any date for which it and SWA272 from PDX to TPA both have award seats available. In fact, I would think an RSA supervisor could even authorize this type of change. (The one who looked at your situation most likely looked only at changing you to published, scheduled service for PDX-FLL; it is not surprising the supervisor could not make that type of change.) You could try calling reservations again before Tuesday. If the first RSA and sup can't make it work, give polite thanks for the efforts and phone back to try again with another rep.With your 1pm deadline Monday, you could book Monday morning flights for $39++ (from either TPA or MCO). Granted it obviously would be more hassle having to go through airport security again.One difference may be that your flight is a summer Sunday. Those have notoriously poor award seat availability, so I think the odds are low in your case.You save about 45 minutes driving to MIA from MCO versus TPA, but you'd be giving up your efficient direct flight to TPA for a 9:40 connecting flight.(FCFree, Bill Owen might be in need of your expert assistance! SWA has PDX-TPA direct but all their PDX-MCO flights are connections! )

If you aren't able to get the flights changed with either tusphotog's idea or through a CSR on Tuesday, you may have to rent a car and split up the drive, finishing it Monday morning.

Don't forget that you can use your RR awards for one way trips. You can book a one-way flight from PDX to FLL or MIA on a carrier with more reasonable fares (or one way award seat availability if you have the miles), and save half of your SWA awards for future use.

I assume you don't have travel insurance? This is going off-topic and at this point only good for the "lessons learned" file, but (IMHO) good travel insurance should always be purchased by anybody who decides to book related air and cruise travel independently.