P4 and P5 in Same Session

Hello Mr.Moffat I wanted your advice. I would like to know if it would be sensible to take P4 and P5 in the same session, or if it would be unwise to do so. If i were to start studying from the beginning of December for the March exam session. I passed F5(52 Dec 2015) and F9(56 Sep 2016) both on first attempt, and I do not work at the moment. Thank you kindly.