Agreed on the sending data to a server and receiving a response with what is necessary, etc. Do they even have the infrastructure to do that at this point? We have no idea. That's if their method even would allow a turnaround with such speed on-the-fly for not yet supported discs.
Let's be realistic. DeUHD is basically in a public testing phase. They could easily do what MakeMKV has been doing for a long time. Allow people to use it for free but have it time-bombed. Either have it stop working after 30 days or give out time-limited licenses for 30 days. AnyDVD has an fully functional trial, as well. Let people test, report back, etc.
The limitation of 8-10 minutes using the DeUHD trial is likely to get people to get aggravated and purchase a fuil license on top of preventing pirates copying UHD discs and then sharing them online. Yes, some UHDs have already been released but not on a mass scale as well as allowing everyone to possibly analyze the software more closely. Given how long it takes to copy a UHD disc the fact you only get 8-10 minutes of playable content makes it painfully annoying and for many simply not worth it. Heck, even with a full license you can only decrypt 2 discs a day.