Helper timer using a variable slider & random timer

Hello, just wanting to know whether there is a way to setup a timer helper that uses a variable slider and a random time between 2 parameters. I have followed this tutorial https://www.youtube.com/watch?v=w2JdFFRT5g0 but require the timer function so that it maintains its time when home assistant reboots?

Thanks in advance.

I’d rename your thread title to reflect your core issue :arrow_up: