Complex sentence: Their final days were spent in shunting service and by 1972 they were all withdrawn, some being sold into industry, like number 1211 which became "Puffing Duggie" at Grootvlei Proprietary Mines (GVPM).
Split into simpler sentences: Their final days were spent in shunting service and, by 1972, they were all withdrawn. Some were sold into industrial service after withdrawal, like no.1211, which became "Puffing Duggie" at Grootvlei Proprietary Mines (GVPM).