There is no nonstop path linking Southwest Florida to the northeast of England, which means booking business class from Fort Myers to Newcastle is really an exercise in choosing the right American gateway. Having routed this itinerary more times than I can count, I can say definitively: the smartest play involves connecting through a major East Coast hub—Delta via JFK or Atlanta, American via Charlotte or Philadelphia, United via Newark or Chicago—before catching a onward European connection that funnels you into Newcastle via London or Amsterdam. None of these three US carriers fly directly to NCL, so the real decision is which transatlantic business product you want logging the long haul, since that's where your comfort budget should go.
My preference has consistently been Delta's One Suite on their A330-900neo or A350 widebodies out of JFK, which offers a sliding door and genuinely restful bedding—ideal before you tackle a tight connection at Heathrow or Schiphol for the final hop to Newcastle. American's Flagship Suite on the 777-300ER or 787-9 from Philadelphia is another strong option, particularly if your RSW-to-hub leg routes through Charlotte, where the walk between concourses is manageable even with a late arrival. United's Polaris seats, especially on the 767-300ER from Newark, tend to have better availability in shoulder season, which matters enormously on this itinerary since award and premium fare inventory to secondary UK cities like Newcastle is thin. My insider tip: book the domestic-to-international connection with at least two hours of buffer at your US gateway, because RSW's seasonal snowbird traffic in winter months can create TSA bottlenecks that eat into tight layovers.
January through March and October into November are your best windows, both for fare softness and for avoiding summer's premium-cabin surge across the Atlantic. Because pricing on this multi-carrier, multi-connection route fluctuates more than headline nonstop city pairs, setting up fare alerts is the only reliable way to catch a fair opening before it closes.
