Does Shaak Ti’s leadership kick-in before Rex’s unique?

@chionophile the point was that all he/she needed was a simple answer, either flat bonus from lead or unique from Rex.

Then people started to spoon feed him/her information eg , both start at the same time.....yeah the start of the battle lol but which one first .then we proceed to do the maths that has already been done.they even said correct me if I'm wrong they wasn't but let's try lol.
Then we have more people letting them know that at the same time is valid as it's before mods like it was even part of the question.

I'm not trying to be rude or aggressive ,just don't think there was any need for the long windedness of this answer.