Originally Posted by oliver2002

After arriving on LX and passing customs and immigration, you can stop by the Plaza arrivals lounge which is not really nice. Just go up one level and thru domestic security. You will end up in the domestic concourse which has a AI lounge that is available to *G ( 'All Air India First Class, Business Class, Maharaja Club members of Flying Returns and Star Alliance Gold customers.'). This lounge is rather bare bones but has showers (bring your own toilettries and a towel as they provide neither) and 2-3 recliners to sleep on. The seating area has sofas meant to seat 2, so you can stretch across them. Catering is limited till about 4am, when they set up breakfast.

I usually try to get on the 9W flight to CCU at 02:30am when I arrive from MUC at 23:15, but that would be rather short for your arrival at 23:55.