I keep my iPhone on airplane mode nearly all day. I usually text via iMessage with the Messages app on my mac. I was wondering if there was any way I can turn off iMessage on my computer and then turn it back on later and get all the missed text messages (with my iPhone on Airplane Mode during this whole process). I tried signing out of iMessage but when I sign back in, I don't get the missed text messages. Thanks!
It is not possible to forward text messages to your mac while your iPhone is turned off or in airplane mode.
While iMessages are "just being moved" within Apple servers, text messages must be first received from your carrier, then synchronized with iCloud so that your mac can receive it too.
With your iPhone being turned off, the chain of delivery is broken.
The following steps show the iMessage way.
Make sure you sync your messages with iCloud on iPhone and Mac.
iPhone - Sync Messages with iCloud
1. Go to settings 2. Click on your Account at the top 3. Choose iCloud 4. Activate iMessage
Deactivate iMessage on macOS
1. Open iMessage 2. Go to settings with CMD + ; 3. Unselect «Enable this account»
Reactivate your account by selecting «Enable this account».
Your Apple ID and phone number are now being used for iMessage on a new Mac. If you recently signed in to "«MAC_OS_NAME»" you can ignore this notification.