Any info about Sprite Editor locks and "Editing data from .psd will be deprecated"

In 6.1 Alpha Sprite Editor changes are locked for .psd and .psb files and when you unlock them you get the message “Editing data from .psd will be deprecated.”

Is there more info about this change to how sprite editor works for Photoshop imports? I’ve been using the pivots for aligning different images and I’m wondering if I should start centering my pivots now and find other ways to align things.