Hi there, we would like to use iMesssage to broadcast messages to a group of users. Is there a limit on the number of users in the group. How best can this be achieved?

We have a requirement in our organisation to send group messages. We have deployed around 10,000 iPhones and iPads to our staff. We need to have the ability to send broadcast messages to this group. Can we do this using Apple's native iMessage functionality. If so how can this be enabled. Are there any backend activities that need to be done. All our users have email IDs and their Apple IDS are the company email addresses. Emails are on Microsoft Exchange.