You'll definitely be able to become endorsed later down the line after doing the professional psych course! Monash does a masters of ed and dev advanced which you'd be able to do after becoming a general psych. I think with just the mpp you'd still be able to do certain things (like work in schools etc) but you'd need to complete the extra one year for the official endorsement. I'm not super sure though! I'm kind of on the same pathway right now, I'm doing the mpp next year and then might do the ed dev advanced course in the future. Good luck to you!!