XSSFTable SetCellReferences() fails with exception if the referenced area is not empty

[superrnovae]

Can be reproduced with this example if you fill the sheet with data and then try to add the table on top of filled data.

It does not happen if we first create the table, then populate cells with data, then update the tables referenced area to match the contents.

It also does not happen when the table is created with CT_Table.

Unhandled exception. System.NullReferenceException: Object reference not set to an instance of an object.   
at NPOI.XSSF.UserModel.XSSFTable.UpdateHeaders()   
at NPOI.XSSF.UserModel.XSSFTable.SetCellRef(AreaReference refs)   
at NPOI.XSSF.UserModel.XSSFTable.SetCellReferences(AreaReference refs)   
at CreateTableInXlsx.Program.Main(String[] args) 

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Update:
Here's the exact place it fails: