PSA: I just checked when the King County (WA) ballots are going out, and they are going out in the mail this Wednesday, October 14th, 20 days before election day.
If you have problems receiving your ballot, like being out of town, you can download and print your ballot. There's an online ballot marking site for low-vision voters. And King County has voting centers for people who need accessible voting options or other help registering or voting. More information: https://kingcounty.gov/en/dept/elections/how-to-vote/ballots/how-to-get-your-ballot and https://kingcounty.gov/en/dept/elections/how-to-vote/ballots/accessible-voting-options.