Definitely check with the school(s) you want to apply to. Some places will not accept the January PCAT, since it's too late in their application cycle. Their individual policies on how they handle multiple PCAT scores will differ as well - although, in general, you are not penalized for taking it multiple times. Some places will take the most recent score, some the highest, some will look at anything below a certain percentile with "concern."
I think taking the PCAT for the third time is separate from taking it in January. As long as the school accepts scores from January, I don't think it matters when you take it.