A bunch of folks have been asking, so I did some digging and was able to get an answer for you folks.

What is going to happen to Datacron Set 2?

Because of recent shift in Datacron release cadence, the first three Datacron sets will all dust during the active period of Sets 4 and 5. This means that three sets will dust into two sets.
  • Set 1 dusted into Set 4.
  • Set 2 will dust, with materials split between Set 4, and Set 3.
  • Set 3 will dust into Set 5, including the additional materials gained from the Set 2 dusting.