I don't think there is a hard and fast rule to that but in my opinion I usually pick, the EA2 on there there second month and assign PSA who have not exceeded 1000VPs in 2months.
The another approach is I assign EA2 without standing orders to my Team leaders to enable get more support and encourage the TLs too.
But for PSA not having to 500 Vps I don't bother reassigning them because I see it as fake motivation to my downlines
