"Do every" codes only take in a value ONCE, so whatever it is to begin with is what it will be. If you want the time to speed up, use a custom event with a "do after" time, which calls itself after that time is up. Even though "Do after" also only takes in the value once, each time around, it's doing the "do after" code freshly, so it will see the updated time.
If you go into the StencylForge, into the game section, and search for "Demo-", you will find my demo tutorials. Many of them use this idea (such as the spawning of enemies for "Demo- Upgradable Shooter" or the creation of platforms in either "Demo- Infinite Platformer" or "Demo- Infinite Climber"), so you can see it first-hand.