Recently some code was added so snapcraft validate would accept a --revoke flag so existing validations could be revoked. When used against staging or prod, this is currently failing with: 'There is already a validation assertion stored for snap-id <snapid> in this context.' This is a 409 error from the store, which in turns gets it from the snap-assertion-service. The problem is that, for a validation assertion, the primary key is: series snap-id approved-snap-id approved-snap-revision So when sending a revoked validation assertion, the primary key does not change and the assertion service fails with 409 (conflict). The fix for this is to increase the revision of the assertion, for an existing primary key. To do that, snapcraft needs: 1- Find out if there is an existing validation assertion for the given primary key curl -s -H "Accept: application/json" "https://api.snapcraft.io/api/v1/snaps/assertions/validation/16/<snap-id>/<approved-snap-id>/<approved-snap-revision>" | jq -S 2- If there is one, check if the assertion has a "revision" field, otherwise assume revision is 0 3- Create the new (revoked) assertion incrementing the revision by 1 4- Sign and push to the store Furthermore, generalizing this concept, these steps should also be applied when "unrevoking", and basically every time an assertion is being built and signed: snapcraft should try to get an existing assertion for a given assertion key, and if there is a match, craft a new one increasing the revision, to avoid the 409 from the assertion service.