Though I can's speak on behalf of the exam team, I'd suggest studying for and taking the exam based on v4.14, if possible. The v4.10 content was very dated and no longer matches current practice as it relates to declarative GitOps. The training was good, I don't regret having taken it last year. I believe it's fair to state the exam was showing its age, however.
Generally speaking, I've seen 90 days before the old version has been removed; however, delaying as long as possible may not permit more than one attempt on that version. In that case, preparing for and taking the updated v4.14 exam is the better option.
OpenShift v4.10 had an 18-month EUS lifecycle and has not been supported for quite some time. Even OpenShift 4.12 is reaching its end of 24-month EUS support in a few months. Although I would like to encourage you to study for and take the v4.14 version, for purposes of prestige it's nice to show successful completion on multiple versions of the exam. But, again, don't delay as if you don't pass your first attempt, it may not be possible to schedule your second attempt on the same version.
