Seniority is directly related to length of service not age, so it is the fact that you have served 30 years rather than are aged 50 that is the (sole ?) criterion.
This is therefore not ageism.
Partially agree, however, a lawyer might argue that if BA offers increased benefits for those with more than say, 20 years service, this would imply that to achieve said benefits one would need to be over 37 and hence since it was not available to anyone younger, age was a factor.Probably do it on a no win no fee basis
