Thank you to all who have answered it
It boils down to usage of DateCalc function which seems to be different between the old (5.10.0 era) and today's. I am searching for the exact definition of that function

In reply to Re^4: Overcoming 5.10.0 vs 5.38.2 incompatibilities by zatlas1
in thread Overcoming 5.10.0 vs 5.38.2 incompatibilities by zatlas1

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