[mikemaccana]

EV certificates require OCSP: Section 26-A of the issuing criteria requires CAs to support OCSP checking for all certificates issued after Dec. 31, 2010.

However as the other poster notes, OCSP stapling includes recent proof that the cert hasn't been revoked the initial handshake, removing additional round trips. See https://en.wikipedia.org/wiki/OCSP_stapling

[mikemaccana]

I should add: OCSP is the baseline requirements, ie. DV SSL certs will also need to support OCSP checking. See https://cabforum.org/wp-content/uploads/Baseline_Requirement...