my 2 cents;-
UDP is a lightweight protocol that by design doesn't handle things like packet sequencing. It does not guarantee that your packets will arrive in order (It does not even guarantee that your packets will arrive at all.) .
Say send command set voltage=1 v, then set voltage=4 v, You might get 0v or 1v or 4v if default is 0v. TCP is a better choice if you want robust packet delivery and sequencing.
If you're limited to using UDP you would have to develop a method of identifying the out of sequence packets and resequencing them or request to resend, but for Arduino is tough task.
a lot people implement UDP with Arduino, I mean neither OP nor this thread please hold fire.
I guess either they drink too much Italian coffee or I drink too much, might be both. 