Please see further update from QuoVadis on the OU field Issue:
Retiring the OU field for public TLS/SSL
QuoVadis will turn off the Organizational Unit (OU) field for all new public TLS/SSL certificates starting on August 31, 2020 at 00:59. This will affect new, reissued, and renewed certificates. Existing certificates with OUs are not affected (and do not require revocation or replacement).