Some people receive pre-arrival before even getting bio/medical done. Some people don't get it at all through out the entire process. Some people don't get it but get PPR instead.
Pre-arrival doesn't really guarantee that the application is passed some people can get it and still get rejected, it's just a piece of paper. I think it fully depends on the officer working on your case.
If you applied online you can link your GCKey account to your application by creating a GCKey account and answering the questionnaires about your application. Keep in mind that only 1 person can link to GCKey so if you have a representative you won't be able to link it again since they've already linked.