I hate it but have been in bed by 8.30pm most nights - enough time to get a few hours sleep before the party starts here . DH and I were night owls, but after 4 months of little sleep we have retrained! It definitely makes a difference too, for me anyway (I am the one who gets up at night). Otherwise perhaps a day nap when your son does - it is not possible here as DD1 doesn't stop!
I believe the trick to changing sleep routines are to persist and use a wind down routine for yourself too!!!! Good luck - it is hard without sleep!