Set static time for Check in messages rather than have it linked to check in time

I would like my check in messages to always be sent at 12pm so I have set it to send 2 hours prior to normal check in time (2pm). However when a guest fills out the online check in and chooses a late arrival time e.g. 9pm they won't get their message until 7pm. Usually their arrival time is late because they have a late flight, and I am always getting messages from people panicking that they are about to board their flight but don't have any check in instructions yet.

Can you please provide an option to send the message at a specific time on check in day, rather than a certain amount of hours before check in.