XPA: Invalid File, Header string A is not found

Importing a text file generated in Xero via the chart mapping toolbox results in an error:
aPAChartMapping
Invalid File, Header string A is not found
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This is despite the Xero file appearing to be correct:
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The cause of this issue is unknown.
As a workaround, adding an empty line before the header (A) prevents the error message from occurring:
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