The --dry-run option exists mainly for this purpose. It will attempt renewal early and use the staging server instead of the production server.
If you want to force the renewal to happen earlier, you can change the renewal period in /etc/letsencrypt/renewal/domain.com.conf (the built-in default is 30 days before expiry, which is in a commented-out setting which you can change to whatever you want, although if you permanently set it higher than 83 days you’re likely to run into problems with Let’s Encrypt rate limits).
You can also perform a single renewal with the option --force-renewal. Running certbot renew --force-renewal will renew all installed certificates using the same methods that certbot renew would have used when it decided that it was time to renew. If you have multiple certificates related to the same domain, or if you run several forced renewals in a row, you’ll eventually be stopped by rate limits. But just one for a single certificate shouldn’t cause any problems.
I used certbot in my descriptions of commands, but this is referring to the same software as letsencrypt-auto, which is the old name for certbot-auto.