OK, I changed it to reject, and tested.
I changed the send limit to 3 and reject on a test account .
I logged into webmail and sent over 3 emails, they all showed as sent. I only received 3 in the destination address, but 1 hour later the other 3 were received even though I have marked as reject.
I also tried sending more than 3 with outlook, they also show as sent in outlook. but again I only received 3, but received 3 more an hour after.
Both outlook and webmail don't indicate that a send limit was reached, they appeared to continue to send.