Given large swathes of blackout dates for every holiday period, six nations away game etc. and the restrictions that only one voucher can be used per flight it can be tough to get value as you can end up using it on a flight where you’d be better just paying cash. Particularly if you have status.

I’ve found value the last couple of years with Lanzarote, Lisbon and Faro (and you could include Malaga and other Canary Islands). Flights are frequent but relatively high priced year round due to the retirees scooting back and forward.