No guidance in the strategems section other than "until the 2nd bound...", or Sequence of play.
In PIP dicing on p 26 it says "The CinC ... dices... at the start of each of his side's bounds..."
If dicing is at the start, then deployment of the concealed command must be after the start.
An online dictionary definition of "until" has it meaning "before", so "not until" means "not before". This is consistent with the above.
Therefore it dices independently, but you know how many PIPs you have before you deploy.
This is my opinion based on the rules wording, I don't know if that is what was intended or if there is an accepted practice.
LAwrence Greaves