Adding border to the edge of post
Replacing get_posts with WP_Query

Using WP_Query-based looping instead of get_posts’ array looping
Text-domain supported copy
Scheduling event to the beginning of the day

Instead of scheduling event to the time the plugin is activated. User
may activate the plugin at anytime, but the plugin is aimed to send the
history email at the beginning of the day
Use plural aware copy and email subject
Fixing copy on email and dashboard