Blistering above the windscreen rubber

Evening all well I decided to clean the car today and it has come up a treat (few deep scratches but have a local paint company who mix up good touch up kits) anyway I've noticed a few blisters around the car. Bottom corner of the passenger door (looks rusted right through which is what I get for not looking after paint), passenger wing (bought it like that and am going to replace it anyway) the one I'm concerned about is above the windscreen is it going to be a rubber out and rub down job with some rust inhibitor or is it a screen out job? Few stone chips on the roof which have started to rust so need to get on those.

have you checked under the side skirts? in particular near the B pillar, the Vectras are known to rot here.
to do a 100% job on roof above windscreen its a windscreen out job.