For future reference and the sake of completeness, here is the reply received by SAG support:
It’s a bug, ForceLogon default was changed in EXX721. But, I’m afraid there is no fix for EXX721 because it’s out of support.
R&D is making a fix for EXX7.3, it is recommended that you upgrade to the EXX 734 (latest patch for EXX73) and the apply the new fix.
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