I too have had some date and time errors on my '720 running production software with the original SkyRadar. On the last couple of flights I noticed the NextRad screen constantly showed the data to be 26 to 32 minutes old, so this morning I took a look at the metars and they were all incorrect as to the actual weather and indicating around -248 minutes old for all reporting airports.
After landing I exited the iFly program and found the date indicating 5/3/2014 and the time off by about 24 minutes. I turned off the SkyRadar receiver, and checked a few other things, then turned off the '720 and headed home. When I got home the time and date are correct?
My theory: I have the '720 set to use ADSB GPS input if available and its not getting time and date info from that source. Today when I turned off SkyRadar a few minutes before the '720, it went internal for GPS data and corrected the time and date after landing. The '720 never acquired sats when I got home, nor did it connect to my wifi.
Any ideas?
David