This is a very minor tidbit in this thread, regarding the 1969-12-31 date you were seeing for the “Last checked” date.
It seems the “date last checked” value was unset, and the process reading it treated that unset value as zero.
The unix (& thus linux) time is measured as the number of seconds since 1970-01-01 UTC. For folks west of UTC (e.g. the Americas), your device will subtract a few hours (e.g. New York is 5 hours behind) for the timezone offset, which means a zero time in UTC will show up as December 31st.
Do what you did: ignore the erroneous value.
Further reading: Unix time - Wikipedia