Date column in xls/xlt worksheet - maintain format

[BankerVanuatu]

Date column in an xls/xlt spreadsheet must have format YYYYMMDD. When this date formatting is set, manual entry of dates in other formats automatically change to YYYYMMDD which is what is required. If dates in another format are pasted into the column then the YYYMMDD formatting is overridden.

Spreadsheet is used to upload payments received from clients

Is there anyway to protect the column formatting so it always results in the YYYYMMDD format (eg conditional formatting?)