Quick question. I applied to York on a letter of permission for summer courses and I checked the "mail to university" box. Do i need to send the letter of permission myself to York since they still have not received it.

Couldn't hurt, though I don't know much about this kind of thing.

You shouldn’t need to send it yourself. Since you checked the box, Mac should mail the letter. However, there is no harm in sending the letter yourself.

The thing is I can't use the Letter of Permission I have at home since my mom opened it and York needs a sealed one. Hopefully the Letter of Permission that Mac sent gets to York quickly.