The substantive point of law will most likely be that OpenAI's salami slicing tactic for becoming a for-profit does not properly fall under the statute of limitations. To think otherwise is basically no different than arguing that you can rob a person twice and not be prosecuted for the second robbery because of "double jeopardy".
The word used will be toll. Basically the clock measuring the statute of limitations can be stopped/paused for certain things. It could be that the victim was under the age of 18 and therefore couldn't sue until they hit 18. Or the incident was concealed, so the victim couldn't take action until the concealment was gone.