It's not as easy as that to call a strike in the uk. Takes an awful lot to organise and generally will end up in the courts for a judge to decide if the strike can go ahead. Not as simple as announcing we will go on strike next week.
UK pilots do sympathise with our AMS colleagues, but if the UK pilot is called out to cover and he/she refuses then they will be down the job centre looking for a new job, there is no protection for the UK based pilot.