I just discovered a nasty surprise while looking through the LSMB code

["Chris Travers" <..hidden..>]

The SL codebase deletes Year-end/GL transactions when a Year-end
report is run under certain circumstances.  We ought to look for
solutions to this problem.

Dieter's comment is:  # if todate < existing yearends, delete GL and yearends

This is in RC.pm around line 109 (109 in my working version, which
will be committed later today to SVN.  The line in the released
version may vary).

Best Wishes,
Chris Travers