Yes, you would exceed 300 (absolute max 400) per hour if there is more than one piece of activity per hour. You have a couple of options:

1) Switch to a "digest" setup where all traffic is batched and sent out combined once or twice a day. That way you get a single burst of 250 mails once or twice a day. Note that when you approach 400 members, your system is going to be in trouble, unless it can throttle mailings to stay under the email caps (send out half this hour, half the next hour).

2) Switch to a "forum" where people sign on to read the traffic. Any good forum software can restrict reading of postings to signed-on members, and not guests (not signed-on). Mailing lists are so 1999!

Another, and what I usually recommend, is using phplist for mailing list, as this can be modified for "batch" sending.

Generally I recommend setting it to about 5 per minute, as this allows you to stay under both the minute limit as well as the hourly limit, while allowing a little "leeway" for anything else you may have sending email.

In cases where you have multiple people replying to the list, it should still only send out based on the limits you specify, queuing the messages for later delivery.

Have you actually been suspended for exceeding 200 per hour? What kind of problems have you had, trying to send at 300 per hour? If you're having problems, it might have nothing to do with LP's limit. I haven't heard anything beyond "400 per hour is a hard stop (suspension), while 200-300 per hour is recommended as your limit". If LP has in fact lowered the limits (again), it's awfully nice of them not to tell us (again)!