Welcome onboard

The availablility of extra legroom / medical (special needs) seats depends on the aircraft type scheduled to operate your flight. Can you let us have your flight details please so we can check for you; where you are flying from, on what dates and flight numbers if you have them? That way, we can let you know the aircraft you are flying on and link you to the seating plan. As you've been told, there are strict requirements for sitting in extra legroom seats located by emergency exits and doors. This is in order to ensure a rapid evacuation if the event arose (hopefully not!). Some aircraft types have seats located by bulkheads that offer more room, and because they are behind a bulkhead rather than by a door, anyone can occupy them. There are also medical (special needs) seats allocated on aircraft for those that may require them. However Thomson Airways operate several different aircraft types so we'd need to know which you were on to advice further. Flights to Santorini are either operated by a Boeing 737-800 (winglets) from Birmingham, or Boeing 757-200 (winglets) from Gatwick or Manchester. If you are travelling on the Boeing 757-200, you might want to request seats on row 2, seats D/E/F as they are extra legroom behind a bulkhead. Although they offer extra legroom, the bulkhead does mean those with long legs can't strech them out. They do offer more room over standard seats though, it's just you don't have room like you would in a normal seat put put your feet under. There is also row 13 seat F that is the row behind the exit row that offers lots of room as there's nothing infront of it that I would advise you try and request if you are on this aircraft type. This is a special needs seat so may be applicable in your case due to your medical condtion. The seats adjacent, 13 D/E are standard seats. If you request / pre-book any of those seats, you should be allocated them and shouldn't be seperated. If you are travelling on the Boeing 737-800, row 1 A/B/C and row 2 D/E/F are bulkhead seats that you may want to consider and are also designated special needs seats for medical conditions. Extra legroom seats on rows 15 and 16 are emergency exit rows so you couldn't occupy those seats. In the mean time, you can view further aircraft information on our What Aircraft? guide (link below).
Darren