Mobile user experience is poor as they may not be able to control which ISP they have access to.
An IP address is not an authenticator by definitions like NIST sp800-63b. It is not a secret, nor is it in control of the user. The MAC address isn't even constant, it can be changed on Android (temporarily) without root.
Android is not interested in EUI-...
I guess the first question you should ask yourself is how your queries look, if the service considers them to be on the verge of violating acceptable use terms.
In other words: What are you trying to achieve, and is there a better mechanism for doing that which doesn't, for example, cause unreasonable amounts of traffic?
Your's is the most comprehensive question so I will provide my input here.
From my testing in Windows Server 2012 R2, I can restore this functionality without rebooting by doing the following:
Unfortunately you have to force the restart of sstpsvc, which also requires Routing and Remote Access to restart, effectively ...
Some VPS has the configuration of enable PPP service, so you can check it and enable the PPP item. The default settings may be disabled, this can cause error:
Couldn't open the /dev/ppp device: No such file or directory
vps config for ppp