Actually, I messed up my calculations again (I put in the wrong dc) it's 83%/99% for 3/4 actions.
Yea I was leaning towards just grabbing the extra action for physical, but 99% odds with 4 actions is just too tempting unless the summer months unlocks something even better. So I'd say something along the lines of this would be a pretty good outline to start with, and obviously modify it as results alongside boons from Sect points come in.
September: 4 actions to get the second physical cultivation milestone, and an action to open meridians*.
October: 4-5 action to reach the first** apprentice mile, and likely more meridians cause we aren't winning a sect point with 1-2 actions imo.
December/January: Everything on Transfiguration.
December/January: Everything on Charms except 1-2 action on meridians in preparation for swapping back to Transfiguration next month.
I'm unsure whether we want Charms, or Transfiguration first, but I think Charms has lower hanging fruit, and that makes me inclined to grab it first. I suppose we can swap in a Charm action instead of meridians if we get enough excess from the first one.
Continue swapping between Charms, Transfiguration, and meridians until the skills are raised to Intermediate skill level.
Afterward the obvious options would be either going for peak second realm spiritual cultivation, or the first*** milestone if we can get it in one month. I'm inclined toward the later as by that point we'd be rolling roughly d28 with 8 Charms if it mirrors Transfiguration in apprentice, and +100 from results with 8 Transfiguration techniques, which makes the +1 to pool from spiritual less crucial whereas potions work for Quidditch.
Once again this is just an outline, and I focused things around a primary topic in the hopes of insuring Rei earns at least one sect point a month.
*Places of power from Astronomy require meridians to use iirc so we'll need some for existing transfiguration techniques plus these. Technically this can be charms if we want them more, but we want an excess of meridians imo.
**This is important as getting it would reduce the threshold for spiritual cultivation to 10 if it mirrors potions, and once we get potions to Intermediate this will make the breakthrough threshold be (8+10)/2=9. This can in theory wait until we push beyond the first 2 spiritual milestones if the math doesn't work out, and allocate any spare actions to Charms.
***If it works like potions it should reduce the threshold for potions to ten.