v6.7.0.2 specifically added a fix for people downgrading from 7.x-series: This is an exceptional maintenance release. Since v7.* the sqlite database is the default cache format. However, all the versions prior to v7.* suffers from a bug where the databases might not be closed properly. This is a fix for v6.7.0.1. This release allows users wanting to downgrade from v7+ (so having the cache converted to sqlite) to v6.7.0 but with the databases correctly handled for sure. Distributions with long term stability support or with long time rolling releases should provide this version while offering the upcoming v7.* offlineimap package. This version should supersede v6.7.0.1.
Added to the tree.