You can create custom dashboard widgets style notifications and display them to certain user roles, set a date range and select from various announce types.
Announce from the Dashboard is a WordPress plugin that allows you to create and show custom notifications, news or update to registered users on your website.
Start by installing ‘Announce from the Dashboard’ plugin in WordPress
Upon activation, visit your admin area dashboard Settings -> Announce from the Dashboard page and select your options.
Announcements can be shown on per user basis, you can create multiple announcements and show them to different users on set date range.