The flights commenced in Nov 89 to New Zealand (Cairns and Perth in Nov 1988) winter seasons only. I actually worked as cabin crew on some of the Britannia Australia/New Zealand flights chartered by Austravel and Travelbag - aircraft were Boeing 767-204ERs G-BOPB/G-BNYS
G-BPFV with intially 258 seats (two rows removed) and later on 274 seats.
Great trips for customers and crew, first one I did we were away on
crew trip that lasted 26 nights! - you don't get that these days.
Service was really good too, a combination of up to 8 meals/snacks served all the way to New Zealand - and good ones at that with free drinks and wine.,
The flights to New Zealand for the first couple of years would route :
Luton-Bahrain-Singapore-Cairns-Auckland and return, with the Christchurch flight alternating fortnightly (returning via Brisbane)
Coolangatta (Gold Coast), Canberra, Sydney, Adelaide, Melbourne also featured with a short series in I think 1989/1990 to both Darwin and Alice Springs.
Laterly flights would depart Gatwick and Manchester instead of Luton, and
would use Sharjah/Abu Dhabi/Al-Ain in Middle East to refuel, then Singapore refuelling stop was changed to Batam.
I think the last flights were operated 1995/6