On 9.6.2012, at 0.53, Adam G Tilghman wrote: > > We're planning to upgrade our site from 1.2.17 to 2.1.x within the > next few months, but we must ensure our ability to revert to 1.2.17 > if problems arise. > > I don't expect our maildir storage would present a problem, > but am less certain about 2.1.x index/control files remaining > readable under 1.2.17. > > Should I have any reason to worry?
1.2.17 can read v2.0 indexes without problems (it has some forwards compatibility code). I don't think I added any incompatible changes to v2.1 either, at least nothing major..