Originally Posted by
Weekend Away
I'm not sure I understand the confusion here. If Delta cancels the flight, OP will have two options. A full refund of miles and cash (taxes) or a reroute at no additional cost (assuming one exists). Those are the options and have always been the options.
A fare difference has never been a requirement to be rebooked if Delta cancels the flight.
If, in the other hand, the OP wishes to make a change to their itinerary, then the new current rules come into play. No change fee but a difference in fare applies.
If DL cancels flight, they will not charge fare difference if flights are rebooked on same days or within a reasonable period. But they will likely not allow the rebooking to be for flights at some point in the distant future with no fare difference, or allow them to be rebooked at a later point in time of the OP's choosing without charging a fare difference.