Definitely start the day when you get him up, if 6:15 is wakeup, then start calculating A times from then.
I would just try to keep it at a general EAS routine, and aim for naps after the age appropriate A time (or cues if you LO gives them), but it may be too hard to try to work it out with daycare (but you never know). After 6 weeks your LO will still be pretty young and you can continue from there.
The EASAEAS routine is pretty typical for short naps, we did that a lot in order to help space out the feeds.