hi there, i am developing software that allows insurance companies to send text messages to their clients when their insurance expires. i want to add a function that allows the system to automatically send these messages n number of days before the expiry date. ('n' being number of days specified by the insurance company. for example:
if John's insurance expires on 25th november and his insurance company has set a date through the system that all clients should receive text messages 5 days before the expiry date. the system should automatically calculate the date and John should get a text message on 20th at 06:00 hours.