Need help with iCloud email limitations!

I received a bulk email from a professional group that I belong to. There are approximately 250 members to this group. I responded to the email with a "reply all" and now I cannot send any emails. I keep getting the message: "You have exceeded your daily sending limits... etc."

Questions:

1. How long do I have to wait for this to "reset"?

2. Is there any kind of a work-around?