12-20-2018 04:19 AM
Today, you can take ACMX 6.4 or ACMX 8.0. You can search on exams on this search page.
I see exams on ACMX 6.4 scheduled through March. However it also mentions:
Notice: Effective November 1st, 2018 the ACMX v6.4 exam enters a "transitional" state, candidates will have 5 months to achieve this certification before it expires effective April 1st, 2019. New candidates should follow the version 8 training path for the new ACMX v8 certification. Click here to learn more
In the past, exams were valid for a certain amount of time (3 years if I'm correct). This has changed to a model where validity is bound to a product/exam version. If you pass the exam now, there are chances that your certification will expire after the exam goes inactive at April 1st; and you will need to do an upgrade exam to get to 8.x.
So if you feel comfortable with the 8.x practical exam, you probably should go for that. If you prefer to do the 6.x practical, and upgrade via a written HPE6-A48 exam, that is possible as well.
Info on the prerequisites and upgrade paths can be found here.
If you have urgent issues, please contact your Aruba partner or Aruba TAC (click for contact details).