Is it better to use one party’s CPF OA for BTO downpayment instead of 50-50 from both?

My partner and I selected our BTO flat and we are waiting to pay our 5% downpayment. We are in our mid-twenties, both employed full time. I have 50k in CPF OA, my partner has 23k. I remember reading somewhere that in this scenario, it’s better to deduct the 5% downpayment solely from my partner’s 23k and keep my OA there to earn more from the interest, before we pay the rest during key collection in 3 years time. May I know if this is a good option or is it even allowed? Thanks!