I ordered EX280V45K but I'm not sure whether it means EX280 with OCP v4.5.
If so, the OCP v4.5 is no more officialy supported and should I contact someone from Red Hat to upgrade it accordingly to a newer version?
Appreciate your advice. Thank you!
If you want to take the EX280V46K exam instead of already purchased EX280V45K, I would suggest contacting Red Hat training people.
However, I think there shouldn't be big changes in the exam, because there is no meaningful difference between the TOCs of DO280(OCP4.5) and DO280(OCP4.6).
 You can find a list of contacts at https://www.redhat.com/en/services/training-and-certification/contact-us#tab.contact-method.1