The T+3 rule means July 13th will be the last date. E*Trade told me the T+3 rule is Trade plus three days for the clearance of funds.
It will not be the 14th. The stockholder on record determination will be based on the 13th. If you buy later, do not expect the distributed shares to come to you; they will not.
There is nothing to agree on. The trade will need three days to settle and it's a fact. It's that simple. Therefore, the trade needs to occur prior to the 15th.