By definition, completion of primary series means 3x sinopharm or 3x sinovac, or 2x Pfizer, 2 x Moderna.
Apparently MOH's call for 3x sinopharm/sinovac had issues with China and visitors from other countries because in other parts of the world, primary series means 2x sinopharm/sinovac.
As a result, there were many reports that those (especially non-citizens in Singapore) who took 2x sinopharm/sinovac and allowed their vaccination status to lapse for 1-2 months, but MOH automatically reinstated them to vaccinated, without third jab. Now, these examples had confused many who had completed the sinovac primary series and due for "booster jabs" (either Pfizer, Moderna or Sinopharm).