In case you missed this announcement, starting on November 2, 2020, subscription and maintenance customers will have access to the current version and the five most-recent prior versions. Currently, access is limited to the current version and three prior versions.
Technical support will continue to only be provided for the current version and three prior versions. But for large projects, as well as for those medium to small projects that just never seem to end, this may allow you to avoid having to upgrade files to a newer version due to the original authoring version no longer being available.
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