You can add an announcement by going to 

Admin > HR > Announcements 

Need help creating an announcement? We have you covered, please click here to find the article.

When adding an announcement, you can see the option to choose a  go-live date.

This means that the announcement will not be displayed to employees until that date is reached. 

Please note: If you add a go-live date and it is in the future, you cannot then send an email – the send email tick box will be greyed out