The first entry is always the pin's source. Overall confidence is a weighted average of how firmly each reference supports the start and end times used above; a reference counts half as much for every 180 days older than the newest.
English Wikipedia says the line is "planned to finish construction and open between Baoshan Railway Station and Yierba Jinian Road in December 2027", a month with no day.
Reports shield launch by China Railway No. 2 Engineering Group on a 1,600 m single-bore section.[1]
Official report on Baoshan Railway Station, due 30 June 2027, northern terminus of Line 19.[1]
Official city announcement of the start of construction, length, station count and route.[1]
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