Rankings Shifting for the Past 2-3 Years

[dragonflydm]

For the past 2-3 years, my site’s organic rankings have been dramatically shifting, ranking well for a few days and then dropping for a month or two, then ranking again for a few days, and then dropping again. During the time of higher rankings, form submissions increase significantly. The ranking increases or decreases are typically between 10-30 spots each time. I’ve done everything I can think of to address any issues: improved speed, limited 404s, changed the architecture of the site, updated link anchor text, etc. Nothing seems to work.

The site has 88% of its traffic coming from desktop, with 9% from mobile and 3% from tablet. The disparity between desktop and mobile leads me to believe that the ranking issues are mobile-related, especially now that Google is using mobile-first indexing.

I thought dwell time could be an issue, but session duration is 2:07 minutes and bounce rate is under 60%, with an average of 2.27 pages per session. That doesn’t indicate any quality of traffic issues to me.

There are no warnings in Google Search Console, and speed is 58 for mobile and 86 for desktop on Page Speed Insights.

I’ve been doing SEO for 12 years, but this has me stumped. My top suspicions are:

• Speed issues on mobile
• Penalties for redirects from old website to the new website
• Penalties for anchor text for the old brand name instead of the new one.

The site is https://dragonflydm.com

Has anyone seen anything like this? Any ideas?