Data from Sector 27 - the first of the TESS Extended Mission - is now available at the MAST archive. All data is in the Southern Ecliptic Hemisphere and covers a region that overlaps the Prime Mission Sector 1 field. This is the first time, TESS users can get their hands on the new 20-second cadence mode. Roughly 1000 stars were observed at this high cadence - details of the targets from GI programs is available on our approved programs page. In addition to the new 20-second mode, there are over 16,000 2-minute cadence targets and Full Frame Images taken at the new cadence of 10-minutes.
Sector 28 is starting to be ingested now too and should complete over the next week. You can always learn what data is currently available at the archive, see the progress of current data ingests, and sign up to get notified when changes happen at the MAST data holding page.