Ian Talbot analysis the development trends of Lahore and Amritsar post-partition. In contrast to the resurgence of Lahore, Amritsar saw its economy deteriorate due to lack of trade links with Karachi and Central Asia. Most of the supply of raw materials and business relationships with Lahore and western Punjab were now cut-off due to Partition. This resulted in Ludhiana becoming the major industrial hub of east Punjab and Amritsar becoming a border outpost with very little economic vitality. Journal can be access in JSTOR (requires registration). Some excerpts.

Sikh and Hindu refugees arriving on ships at Bombay Port, 1947. Also refer to this article for more details on how these refugees arrived from Karachi, https://www.gatewayhouse.in/bombay-karachi-linked/

Irfan Habib, Romila Thapar and Harbans Mukhia