Custom Message based on Date

Morning team is me Again! Thanks in advance for your help - Imagine we're an hotel for the following use case -

We're wanting to send a message based on date, however, can we setup the trigger in such a way that will only send messages if the "check in" custom date fiel is Monday-Thursday? We're wanting to send a message to guests who might be staying say a MONDAY and after they checked in, we trigger a message offering the next day (Tuesday) at a discount(we dont need validation if Tuesday is avaialble, we just need to ensure the message goes out to M-TH folks - this to encourage the sale of what we called orphan days (Monday - Thursday) we're trying to upsale -