Well, the last time there was any official statement on this, was two and a half months ago and @Modiphius-Jim
a) confirmed that there is more material to come, but
b) also stated that they were “still working out the release schedule and trying to figure out where it all fits in”.
@Modiphius-Jim – any news on the schedule?
@Grendel: There are two free adventures in the ‘Modiphia’-magazine (which has also gone very silent, recently, now that I mention it…) that will blend in perfectly wherever you want it. What I have read from the buyable adventures (These are the Voyages, several stand-alone adventures) is actually quite good (and I never used pre-generated adventures before STA!). If you want to stick to free material, Continuing Missions is always a good point to start searching. 
On the cliffhanger: In case you have not started with the season finale, yet, I would suggest to drop in a few stand-alone episodes, before.