We wrote a post on the GoDaddy blog about our experience: https://garage.godaddy.com/webpro/wordpress/how-to-get-your-theme-published-on-wordpress-org/

Many themes are published in a few weeks or months, but if you’re not proactive with your review, it can take longer. Our approval process took nine months — and some themes have been in the process for more than a year.

If we learned anything, it's that we needed to be (gently) pro-active. The review team was overwhelmed and the theme authors who advocated for themselves probably got published faster.

The Slack channel was a big help ... that was by far the most useful source of advice that we found.