Error removing attestation from directly assigned group

When a group has directly assigned attestation, attempting to unset it by editing option to "No, does not have attestation directly assigned" returns an error on submission:

Error: Expecting something which can be converted to boolean, but is null or blank: 'null', Problem calling method editGroupAttestationSave on edu.internet2.middleware.grouper.grouperUi.serviceLogic.UiV2Attestation

Stack trace attached. In my case, the stem didn't have any attestation, so I was expecting the change to just delete the attestation attribute, or blank out the fields or something.