I currently own a Hisense Roku TV. I was just wondering when then the new Roku OS 11 will be available for my tv.
No one can tell you that. It takes months for the millions of Roku devices across the world to get the new firmware. I own 3 TCL Roku TVs and they are still 10.5
My TCL 55S425 usually receives OS updates about 3 months after the announcement blog post. It's disappointing, but understandable given the scale of the task.