Agreed. I've been through something similar a couple times before. I recommend calling to make the appointment before OP gets back, and ask the place to send a confirmation via email.
They'll tell you that it still may not stop you from getting a ticket, but if you get them to send that to you, then the officer who pulls you over may be nice about it and let you off with a warning.

On a similar note, I had a dead headlight and the officer that nabbed me was super chill about it. It was Tuesday and I told him my boyfriend at the time was going to help me with it on Thursday (which was all true, if that matters to anyone here.) Instead of fining me and calling it a day, he gave me a written warning that required me to show up at X-location in something like 7 days to prove I had gotten it fixed.

Planning ahead seems to greatly help with making the punishment lighter.