That’s not a meaningful issue here. Either snoop competently or snoop wire traffic, pick one.

In the snooping-mandatory scenario, either you have a mandatory outbound PAC with SSL-terminating proxy that either refuses CONNECT traffic or only allows that which it can root CA mitm, or you have a self-signed root CA mitm’ing all encrypted connections it recognizes. The former will continue functioning just fine with no issues at providing that; the latter will likely already be having issues with certificate-pinned apps and operating system components, not to mention likely being completely unaware of 80/udp, and should be scheduled for replacement by a solution that’s actually effective during your next capital budgeting interval.

That’s usually done not on the network side but through the device itself. Think MDM and endpoint management.