Hi, 

I purchased this router in US arround 2019dec, than I moved to Hungary and it works well. In 2020 I was able to update the firmware once and sience that it says no new update.

Now I add a Range Extender RE315 and wanted to use them in OneMesh mode but it said the Router is not prepared and firmware update required. I saw only the hardware model v2.6 is getting further firmware updates which are OneMesh compatible. 

Can you advise if there is a firmware for my model which can manage the OneMesh?

Can you help me to fix it?

Thanks