It's not uncommon to want to schedule your message to be sent to multiple places at once. Using the Slack scheduler advanced scheduler, this is easily done.
- Visit any channel or conversation in Slack (if you're not sure, just open up a direct message with yourself)
- Type /schedule
- Hit send
You'll now have the advanced scheduler open in a modal.
- Complete your message
- Specify any timezone (it will default to your profile's timezone)
- Set the hour and minute to schedule
- Choose the user(s), channel(s) and / or conversation(s) you would like to schedule the message for.
Users are direct messages with other people in your team. Channels are public channels in your workspace. Conversations are group chats and private channels that you're a part of.
There is a limit of 50 total channels that you can schedule across. If you have a use-case for needing more than 50, please reach out.