When is the deadline for registration for parent volunteering for P1 admission?

It depends on the individual school. For the school I chose, the registration starts in Aug-Oct when my child was in her K1 (5 years old).. You should start to call the school that you are interested in when your child turns 5 years old to check on the exact dates of registration and submit necessary forms. Most of the schools' PV registration starts in the last quarter of the academic year however some schools will open PV registration will start even earlier.