We would also advise to set up all your bill paying via automatic deduction from your checking account. No worries.
Or leave some checks with a family member and have them collect your mail and pay your bills for you.
If you do have mail shipped to you, plan on your first shipment going to Tok, Alaska. Everyone has to pass through Tok going and leaving Alaska. Have it addressed to you, c/o General Delivery, Tok, Alaska (and the zip code). We always use Priority Mail. Allow 5 days to get to you. Then you can have additional mail sent to you the same way as you're traveling in Alaska but pick a small town - not Anchorage or Fairbanks. As full-timers, we've had mail sent via General Delivery all across the country, including Alaska, for 16 years.
Definitely don't plan on having mail sent to Canada or the Yukon. It has to go through customs and it can take weeks to get.
Have a great trip!