Smartwings leased a 737 to Sunwings for the winter season and it has been returned after the lease, albeit with a little detour to pick up stranded passengers: Toronto - Panama City - Havana - Halifax - Keflavik - Prague (source www.skyliner-aviation.de) And another one off lease from Air Transat flew Toronto - Puerto Plata - Toronto - Keflavik - Prague.
KLM returns to Australia after 20 years. Multiple flights planned, possibly also New Zealand. The first is on it's way (stop-over in KUL due to lack of crew) as KL827. You can track it on FlightAware (FR24 is messing up flightnumbers).