Once you have passed your PJFT, don't wait for your AFCO to contact you- give your careers adviser a call to discuss the way ahead.
If there's a Royal Marines Acquaint Day (RMAD) in your area it's worth asking if ou can go on one to see whether you're ready to go. Generally your Careers Adviser won't book you onto a PRMC unless they are fairly confident you will pass PRMC & the applicant thinks likewise. We don't just book a PRMC because you passed the PJFT - for all we know you can only run 1.5 miles, have never timed yourself at 3 miles, can only do 20 press-ups, or only 2 pull-ups and are not worth sending yet.
Good luck anyway.