Hello George,
Yes you are correct about access to previous editions. We are a PMI Registered Education Provider and are required by PMI to stop providing access to outdated materials. So when PMI publishes a new exam, which requires us to also publish a new version of our training materials we have to close the old edition.
This means that if you purchase The PM PrepCast SIXTH edition now, then your access will end probably in about 2022. PMI is currently working on the PMBOK Guide SEVEN. Publication is expected sometime in 2021 and that will lead to an exam change in 2022. At that time we will release our own seventh edition and close access to the sixth edition.
