QUOTE
Every time you submit a separate entry in any format, the AB system regards it as exactly that. You will get different exam dates for the candidates you have entered.
I've had to submit separate entries a few times, but I've always emailed and asked for them to be examined at the same time and there's never been a problem.
There was one occasion when the last candidate of the first batch withdrew, and as it was a separate entry the AB wouldn't let me bring the time of the second batch forward. They put someone else into the gap, and although he went in on time the examiner spent ages with him so by the time my second batch started they were running really late!