An expired certificate should not cause that. I'd be very surprised if they did not have a cryptographic timestamp [1] on the driver signature. The presence o

An expired certificate should not cause that. I'd be very surprised if they did not have a cryptographic timestamp [1] on the driver signature. The presence of the timestamp allows the signature to be verified after the signing certificate has expired. 1 https://en.wikipedia.org/wiki/Code_signing#Time-stamping https://en.wikipedia.org/wiki/Code_signing#Time-stamping