The significance of the date 2009-01-01
I discovered this feature when working on D365FO for Retail. Store transactions were synced back into D365 with a datetime field which had the value 1753-01-01 (the mindate of the datatype on SQL server). The mindate in D365 is 1900-01-01 which is greater than 1753-01-01 so you might expect that D365 would return 1900-01-01 instead of 1753-01-01. However that is not the case. When the transaction was read the date returned is 2009-01-01 instead of the true value 1753-01-01. This was discovered when looking into problems with the field RetailTransactionTable.ReceiptDateRequested which looks to be related to KB 4058850