I immediately though of the GetTickCount win32 function, which, as you said, wraps around to zero every fifty days or so. A lot of programs would crash if you left them open for this long.
In our debug build, I added a registry key that would start the concept of time at 49-ish days, so that we could test that everything was working without waiting 50 days. However, before we shipped, the intrepid test team did actually run the encoder for 50 days to prove that it worked. (On Windows NT, of course. Windows 95 with good hardware and drivers was perhaps more stable than its reputation, but still...) Though TBH we definitely wouldn't have delayed a release by 49 days if it had failed at the last minute.