In the past our Australia and New Zealand flights did have many more stops and the routing did change over the years.
I don't think that the BA009 ever operated the route the OP posted operated, I cannot remember it going via BOM and MAA.
The crew normally operated around a 10 hour duty day so some days there would be one long sector and on others a double sector.
Trips down to Auckland were 21 day trips for cabin crew, the flight crew had shorter trips as there was a base in Sydney.