congrats on the new baby.
as for "when"........too many variables: support system at home, level of pre-prep, level of involvement of parents (sad to say but some parents never really connect with the new baby...). Best thing is to set up a system, kind'a like triage and some point someone will have to take one for the team lol. We set it up so that we would take turns getting up in the night, so that at least one of us would get good sleep. The next night the other would take the time. And remember, if "you" aren't healthy and operating at good efficiency, then nothing you do will be very helpful. Use the weekends or open days, to stock up; cook so that you can have left-overs, or freeze extra (soup stock, spaghetti sauce, etc). Once you get more settled in a pattern, then you will start getting your "work" life back on track. Good luck.
ps......you can do this even if your wife is breast feeding, either pump or I would use pillows to prop the baby in place and my wife would never even wake up lol.
and our oldest is now 24 out on her own, and I still get calls at work for the occaisional questions or help, so once you've started........they will always be in your head.