Signature behaviour depends on whether the form is reset to draft or rejected.
When a form is reset to draft, the main form signature fields are cleared. Signature fields in subforms are not reset.
When a form is rejected, no signature fields are changed. Only the form status is updated.
This works by design:
Reset to draft is intended to return the form to an editable state so it can be completed again. As part of this process, the main form signatures are removed.
Reject is intended to mark the form as not accepted while still preserving the submitted data, as the form has already reached its final status. For this reason, the signatures remain unchanged.
Note:
This behaviour applies to standard forms. Custom forms with custom scripts or logic may behave differently depending on their configuration.