@Kevin_Z 

thanks Kevin for the reply. But the issue is that this item WAS listed as having that update in the future. Even the wirecutter review describes it (the A20 which is the same product) as having this feature coming. You've got to do better than just pointing me at the OneMesh compatibility list. You need to explain why it was excluded from having this feature added. 
 

@Kevin_Z from the wirecutter article: "The Archer A20 isn’t compatible with mesh extenders yet, but TP-Link is planning to add OneMesh compatibility in a firmware update."

@superdifficult 

Hello, sorry for any inconvenience.

We don't actually suggest our customers purchase any device for a feature that is not supported yet, as plans will change and the compatible device list will be updated regularly. We actually have no many details about why it doesn't support it.

Good days.

@Kevin_Z I am deeply concerned about this. I also purchased this router with it being 'future ready' for mesh networks. Now the plans have changed I am left with an incompatible router. I'd like to hear from TP-Link about supplying us with an upgraded router?

@bouc 

Sorry to know that you purchased the router for the "planned" feature, if this functionality has determined the choice of equipment, it is suggested to get one that has already supported it, you can return the router to the place of purchase as not as described.

Or you can try to contact the local tech support to check if they can help:

https://www.tp-link.com/en/support/contact-technical-support/#Hotline-Support