Chennai is 5.5 hours ahead of London during GMT, and 4.5 hours ahead during BST. When it's 12:00 PM in London (winter), it's 5:30 PM in Chennai. India does not observe DST.
India uses IST (UTC+5:30) year-round while the UK switches between GMT (winter) and BST (summer). The difference is 5.5 hours in winter and 4.5 hours in summer.
Morning to early afternoon works best! 9:00 AM - 1:00 PM London (winter) corresponds to 2:30 PM - 6:30 PM Chennai. Good business overlap.
Chennai is a major industrial and IT hub in South India, known as the "Detroit of India" for its automobile industry. It's also home to many IT companies and BPO centers.