They can write as much code, complete as many badges and run the Simulator as long as they like. If they have 1-year LearnToMod accounts or recurring 1-yr LearnToMod subscriptions, they'll get 1 year of access to the website and minecraft server (with a 100 hr monthly limit). 


If you have a legacy LearnToMod teacher account (If your teacher account was fully set up and created prior to 2021), your students will have 2 server hours a day, unless you request otherwise, and unlimited access to the rest of the website until they're unenrolled from your class.