Scheduled messages
Let the bot post on time: once, every few hours, every day or on the weekdays you pick. Premium has it now, every server from December 12.

Posts that arrive on time
A good morning every day at nine, a reminder before the weekly game night, an announcement that goes out on Saturday while you are away. Write the text once, pick the channel and the time, and the bot posts it, in the time zone your members live in.
Choose once at a date and time, every 15 minutes up to once a day, every day at a time, or weekly on the days you tick. A message can ping one role in front of its text, and any other mention in it notifies nobody, so a reminder never pings the whole server by accident.
How to try it
Open Scheduled messages in the dashboard, add a message, pick its channel, write the text and choose when. Switch it on and save. The list shows when each message goes out next, and when a one-off was sent.
Scheduled messages are in Premium early access until December 12. After that every server runs 3 for free, and Premium runs 50.
Try it on your server
Add ZombyIO to your server and switch it on in the dashboard.