Hi Maria! I think this is personal preference! For me, I think I would review the questions after my first attempt, then retake the exam shortly afterward to test my retention of the new information. I might take it again in a few months after spending more time studying to assess longer-term retention.
In order to ensure I have enough material to get a good sense of test performance closer to the NCS exam, I’d recommend saving at least one exam to take for the first time 4-6 weeks out from the exam.