the physio will be able to tease out what structures are actually involved (tendon, muscle, bursae, etc) The diagnosis you were given is a general term. And don’t fret, I know some patients when they hear the word “syndrome” get worried…try not to.
typically, SOME riding is allowed, keep the power down a bit and avoid lower cadence range (stay 90-100) until you see PT.
Most likely GTPS is tendinopathy of gluteus medius tendons. Treating it as such is will most likely lead to resolution of symtoms. Read my posts in the proximal hamstring tendinopathy thread, the achilles tendinosis thread and you will be able to treat this by yourself if you dont get good help from your physio. Good help is a modern understanding of the syndrome and using loading as treatment. Any needles, poking, prodding, rubbing with metal tools etc is bad help and you should respectfully decline further treatment.