@Enkniham 

Forget it.

The last fw update is from november '22 (v2) and from march '23 (v3)

  @Enkniham 

So I had an AX21 v3 that had VPN client wiregard and it works great.  I made an assumption that the wiregard VPN was to remain going forward.  I purchased 2 additional AX21's and the have version 4 installed or in initial setup I upgraded to latest firmware....  Wiregard not supported apparently and not sure how much research or how I would know wiregard VPN not available prior to purchase.  I looked at downgrade hardware version to 3, but tp-link mentions downgrades not recommended and can damage the router.   I have basically been pleased and well served with this router.  I could go OpenVPN with those two version 4.  I prefer the wiregard but seems that is not going to happen unless a downgrade is actually a real undamaging hardware option.  Has the downgrade been tested at all by tp-link?

Thank you for review of my questions in advance.

Mike

  @IndyMike 

Hi,

"Firmware" refers to a certain type of software.

The hardware version of the router can only be up- or downgraded by replacing the hardware. 

So, you would need to return the AX21 V4.6 to the retailer and try to find another retailer who still has AX21 V3 in stock. Although, I guess that probably 99% of retailers won't be able to tell what hardware version they have in stock. The best chance of getting an AX21 V3 might be at a physical retail store, because there you can see the hardware version printed on the sticker on the retail box.