If you want to practice the towers, Here's the link.
Intense/Remorseless Towers: https://web.roblox.com/games/3240225109/Beginner-Practice-Time
SC (Soul Crushing Towers): https://www.roblox.com/games/1384058178/practice-time#!/about
ToGaH (Tower of Glitching and Healing): https://www.roblox.com/games/4681107263/ToGaH-Practice-Time
ToSM (Tower of Strategic Mechanics): https://www.roblox.com/games/4681108805/ToSM-Practice-Time
Remember, Cheating/Exploiting in JToH in general may result getting you banned!
Now that Roblox has added the option to change your FPS cap in the settings, speedrunning up to 240 FPS is now Allowed. Yippee !
To Be Clear: Memory writing below 60 FPS for things like lag clips is still not allowed cause that takes external software