As for announcements there might me many users email which most of the host do not allow to send at a time. So this plugin send announcement emails using cron at a set interval. You can set that interval in Front End PM PRO > Settings > Emails
Please check following
1. Cron if working in your website.
2. Change email interval in Front End PM PRO > Settings > Emails and wait that time
There are two intervals. There is the e-mail sending intervals which is at every 5 minutes and e-mail sent per interval is at 200. I don’t feel comfortable with your terms. It says that you can do anything with my site?