BA claims such a cut will help them slash their £3.7bn pension deficit by almost £800m. THe government has also moved in this direction recently, switching public sector pensions to the CPI rate.
You can understand why BA staff are angry: the CPI rate is currently 3.1%; the RPI, which includes housing costs, is 4.6% (recently fallen). A big difference. Already some existing BA pension trustees have quit on the development.
The Airways Pension Scheme (APS) was originally set up to adopt whatever public sector inflation index was used. And that has changed. Also, pension members are also angry because they made very clear back in the 1980s that they wanted to retain the RPI link - despite cash offers to change.
However APS trustees still have the discretionary capacity to not fall in line, as well as award any discretionary payments. They will also have to acknowledge popular support. If any overwhelming majority of APS members support the fight - as looks likely - they will have to tread carefully.
What price is a promise - and can a promise simply change?