Appreciate the info, for timed entry ticket we aren't able to select the time we wanna go in right?
Asking because I read that its nicer at night, but then would the ride still be available during then?
If you buy the express pass through USJ's website, you can select the timing (provided it is still available; not taken up).
If your express pass has entry to both SNW and Harry Potter, then the selection comes from a variety of combinations (eg. SNW in the morn, then Harry Potter in the evening, vice versa etc).
If you buy through Klook, the timing for the timed entry tix will be decided by Klook (meaning you are unable to choose; as stated in their T&Cs).
For both SNW and Harry Potter, both day and night have their charms.
In terms of crowd, SNW is packed whether it is day or night. Rides will run till USJ closes.
For reference, Mario Kart ride is consistently 110-120 mins wait (for non-express pass).
Harry Potter wasn't that crowded though.
Do take note of the operating hours which can affect your strategy.
The closing time can range from 7pm to 10pm, which you can check on USJ website.