Merry Christmas
You need 400 within the first two chapters with the one, I know this is possible cos I got 400+ by the end of chapter 2, then switch to the other and get the rest of the points for the other company.
It is available in chapter 4, but you can only do the moonflow
Then in chapter 5 you'll get a hotspot in the Calm Lands, but leave it till last so you can do the rest of spira as the HS will appear if you've got at least one company to 400 points.
I think that there's 1000 points available in total, you only need 400 each, so theres 200 points spare should you screw up.