You didn't mention what kind of data you're interested in. There are many types of data in SkyDemon, from static chart data to live weather and NOTAM data. Any briefing pack you print should have a footer saying the AIRAC data of the charting data being used. Your NOTAM briefing will display a large red banner if it is out of date.

TAF and METAR will have a date and time of issue. Any other weather data such as winds, cloud base and precipitation forecast should always be cross-checked with other sources.

The fact that it doesn't come up with a banner asking you if you want to update it.

It's been a couple of years since I used SkyDemon but I recall that the flight details panel for a planned route had a banner at the top that would be displayed showing either the last download date and time or if newer data was available.