Situation: an O12 player begins the game by rolling a WIP14 lieutenant roll. Their opponent wins and is deciding whether to pick initiative or deployment. They ask 'how many command tokens do you have?' When does this become open information? The earliest a player can spend tokens is during the 1st player's deployment, to reserve an extra model. For reference: the answer to the question in this case will reveal exactly what the O12's player is - either Cho or an Alpha.
From what I can tell, your number of Command Tokens depends on the skills of your list and will be present for the entire match until spent. I.e. it becomes open information as soon as you pick your list. Also Omega.
I trusted the O12 player who asked me the question but good point about the Omega. So we're thinking at list choice? Functionally revealed simultaneous with revealing Lt WIP?
Yeah, but keep in mind I'm just unable to find anything that says when they're generated at a particular time, it's fully possible I missed something
Given that you can use CTs during Deployment, i would dare to say it is an info to disclose BEFORE. Exactly when, well... No way to know!
Maybe a bit of a stretch, but absent any more explicit rule: the Lieutenant rule has this bullet: +1 Command Token. The player that takes this Trooper as their Lieutenant will have one extra Command Token for the match. "The match" is about as broad as wording can get - possibly broader even than "the game" given that the initiative roll happens "before the game begins." So arguably, if you have your command tokens "for the match" you have them right from the very beginning. Possibly you even have four before you choose your list, and then gain a fifth as soon as you choose the list with the Alpha lt :-)