If you mean the usual Jain Chauvihar cutoff at sunset, then for Mumbai on 14 June 2026, sunset is 7:17 PM at Chhatrapati Shivaji International Airport/Mumbai. So Chauvihar should start from about 7:17 PM. ( aim-india.aai.aero)

For extra caution, some people keep a small margin before sunset; the same AAI table shows twilight ending at 7:41 PM. ( aim-india.aai.aero)