I will have to go back and research the rules later when I have more time, but it is my current understanding that the vote of a delegate who is “bound” to a candidate is recorded for that candidate on the first ballot regardless of what happens prior to the vote. Delegate who are “unbound” can vote as they please. Most delegates are “bound”.
Of the total 2,472 Republican delegates, 1,719 are pledged ....
700 is a lot of unpledged delegates