Typically, a full session lasts about 45 minutes to an hour. A refers to sessions that extend beyond 90 minutes, sometimes up to 3 hours, allowing for deeper purification.
This YouTube sequence includes warm-ups, asanas, and Ujjayi breathing to prepare you for home practice. Pranayama & Chanting Guides: long sudarshan kriya audio link
Many practitioners report a significant "weight" lifting off their shoulders after a long session, often releasing suppressed emotions. Typically, a full session lasts about 45 minutes to an hour