Create automatic text if it is already due date

I am looking for a way to create automatic text in cells for my table of contract letter list.

For example if the expire date is January 2018 (which is now), then it is automatically written on Remarks table "Please extend the contract".

Client Name	Effective Date	Expire Date	Remarks
ABC	Jan-17	Jan-18	Please extend the contract

Thank you.

Do you want this to take effect on the 1st of the month only or a specific date within the month?