Getting Countdown to Next Event on Calendar

I’m looking to get on-the-minute updates to node-red on the next calendar event. I’d like to move away from calendar event offset. Input date_time will not work if the countdown is longer than 24 hours. My idea is to have an automation in home assistant to set an input_text to a DD:HH:MM format and then have node-red do the rest. Perhaps home assistant can be made to accommodate days in a countdown. Any other suggestions?