Reply To: The Mysterious moving master text frames

Here's my guess: You added or removed a single page somewhere, causing left hand pages to turn to right hand pages (and vice versa). This is a classic problem in InDesign (and QX before it). The overridden master page items (frames you've put stuff into) get locked into place and then when the page moves, ID has to “reapply” the master page to it, causing the heartache you're experiencing.