Prior to SP3, when a clip was transferred into tether that qualifies for a proxy, you would see Pending Render in the Library. When you went to load that clip to the desktop IFFS would prompt to render the proxy. Confirm, and all is good. Now in SP3, when you load such a clip, there is no Proxy Render confirm and the desktop tools don't allow you to do anything with that clip as it warns "this clip is still being rendered". You are unable to manually Regenerate Proxy, take out 3:2 or even run it thru CC.
Well, it's not ideal to push clips to a smoke/flame system and expect the end-user to sit there waiting for proxies to be generated. When possible, the wiretap app should generate the proxies.
However, it's possible that the behavior changed (or a bug was introduced) between SP2 and SP3. If this is problematic for the customer, please escalate through support. They may have a workaround too. Not being able to use a clip without proxies pretty much invalidates most Wiretap workflows with proxies.