Is Gangtok Helicopter still in operation right now?

My flight lands at Bagdogra at 10:05 am. On STDC website, it says there’s a helicopter that takes off ar 10:40 am from Bagdogra and reaches Gangtok at 11:05 am. Has anyone tried this? I’m wondering whether to book right now or go to the booth in person after the flight lands as I’ve heard reviews stating they don’t take off until they get all their seats filled, even if it’s well past the scheduled time.