how long does it take for someone to be classified in ontario? If they've already been to the pen before will it be a quicker process or is it always around 3-4 months?

I beleive its 3 months regardless if they have been there before.

are you talking about the initial intake classification? it's either 70 days or 90 days, depending on the length of the sentence.

Just to add that the intake is not shortened if someone was previously sentenced to the pen. That said, I have heard that the intake can be refused by an offender, which will likely mean they will be sent to a maximum security penitentiary.