The UI has been revamped. The famous "Despair Meter" (which affects the ending) now has visual gradients and triggers hidden events at 33%, 66%, and 100%. Once the meter hits 100%, the protagonist loses the ability to reset time for three consecutive loops, forcing the player to watch the degradation unfold helplessly.
The subreddit r/NTRgames has a megathread for v1.40 walkthroughs. Kegani Laboratory also posts patch notes on their official blog (Google Translate required). Time Loop NTR -v1.40- -Kegani Laboratory-
The loop mechanic is managed via a that fills out as you replay days. Important decisions are time-stamped (e.g., "Day 1, 4:00 PM - Go to the arcade alone / Follow Saki after school"). The UI has been revamped