Many employers have "schemes" of one sort or another. Employees and/or pensionners "benefit" from schemes.
Very few of the schemes have been really tested in Courts.
One similar scheme for a very big Co was post-retirement BUPA/Health Insurance. (I say Very Big Co advisedly. BA is a Very Little Co. The only Big thing about it is its Pension fund. It is a little Co with a huge pension fund deficit attached.)
Senior Staff - including all the ex-Directors, who left this very big Co were entitled to Health Insurance along with their pension.
The first thing that Big Co did which started a bunch of QC letters was change from BUPA to another, cheaper provider for the pensionners.
QC letters were exchanged. Nothing happened. The change stayed in place.
The second thing was that the benefit was stopped at 65 years of age. More squealing, and more letters from QCs and ex-Chairmen - who were mates of the retired Directors.
Huffing and Puffing ex-Chairmen got nowhere.
Having got through that lot, the Co simply stopped the practice, so no-one got anything.
As a tip for you BA pensionners who can no longer go and see Auntie Maud in NZ, have a look at what "BA" or whatever it is called to-day are doing for the Directors Staff Travel Scheme. Look at both EDs and NEDs.