Copying data from a Calc spreadsheet to a Base table

My project is to replace a large Excel spreadsheet with a Base database, using LO 5.1.1 under Windows 10.

I am trying to populate a Base table from a Calc spreadsheet. They both have the same format; (because of earlier difficulties getting the data types to match I actually created the empty Calc spreadsheet from the Base table, then filled it with data from my pre-existing Excel spreadsheet).

My problem is that Base doesn’t like any of the Date fields. In both Calc and Base I have formatted the fields to English - Australian DATE format D/MM/YY. When I copy the data and paste (Append) in the table I get the message
“Value too long in statement [INSERT INTO “People” () VALUES (?,?,?,?,?..)] Continue anyway?”
The message is fairly unhelpful because it doesn’t tell me where the problem is - it lists every field in the table and then just gives a series of question marks for the values.
If I respond “No” to the “Continue anyway?” question I get no data entered into the table.
If I respond “Yes” it puts the data in except that it leaves the date fields blank, so presumably it thinks the date fields are “too long”. However, as stated above, they are both formatted identically as D/MM/YY and contain valid dates in this format.

Just ran test using LO Calc date used: 1/01/16; 1/02/16; 15/01/16 and pasted into Base table without a hitch. Maybe a bug in 5.1.1