@JKN56 

I am experiencing the same issue.

The 10 Mbs limit looks like a hardcoded value somewhere.

After updating the software to 1.3.3 Build 20240628 rel. 37017 I noticed the ability to set a rate limit (max download and upload speed) per device (maybe this function even was before the update, I am not sure). By default, it is disabled, which means - no rate limits, however - when I changed it to 50 MB, it seems the download speed on the device configured by VPN was increased to 15mbs. However, maybe it's just a coincidence.

But anyway, some issue exist.

When I use a VPN client on the Router I have only 10mbs from 80-100 provided by the Internet provider. When I am using a native VPN client (on my Linux) for the same VPN provider speed is fine.
 

  @mkravets Yes.  Sounds indentical to my experience. Curious what VPN you're using? 

I'm using Private Internet Access (PIA).  It seems like everyone using the VPN client on the router should be having this problem and complaining.  I sure am not happy.  I was hoping that there would be a software fix but I'm guessing it's the hardware that just can't handle the overhead.