A couple weeks back I got his T4 slips (tax stuff). I told his gf to get him to come get them and he still hasn't. She messaged me on Thursday and said if I put them in the mailbox they'd come pick them up on Friday... they didn't. So now I have 3 letters to him in my mailbox just waiting for them to come pick them up.
How long should I wait before just writing "return to send" on them and mailing them back?