Consecutive Years on Sea Duty

Hi everyone, Does anyone know if there's a maximum number of consecutive years someone can serve on a sea tour?

I completed my first tour from 2017 to 2022. I'm in a dual-military marriage, and due to that, I was sent back to sea duty for another 3 years. I'm now wrapping up this tour, but I'm being told I might be extended beyond 8 years because of manning issues on my current ship.

Any info or guidance would be greatly appreciated. Thanks!