If it is, without requesting user authorisation, then that's an illegal act under the UK Computer Misuse Act (and the USA's CFAA I think too) - modification of a computer without authorisation.
I look forward to joining your class-action lawsuit.
Besides that, this sort of "but we hid something in the t&c-s so now we can shit on you" is the sort of thing I expect from over commercialised companies, not from what was once a paragon of the FOSS community.
FWIW class-actions don't exist in UK.