How to update one column in table from select statement?
UPDATE syntax:

UPDATE [table]
SET [est date] = toCONVERT(datetime, 
                           SWITCHOFFSET(CONVERT(datetimeoffset, table.[utc date]), 
                           DATENAME(TzOffset, SYSDATETIMEOFFSET())))
WHERE [utc date] &gt; '2017-10-01'