I think I see what you are doing...

You can book your desired route, now that space has opened up, and then if/when there is a schedule change you can decline their alternate flights and ask for a full refund of the miles. Yep, you can do this. Just be aware, that if there is no schedule change you would have to pay the $100 to get your original miles back, but that is no worse than if you did it originally.

Of course, if the schedule change has already happened on your booked reservation, just call up and request to be rerouted on your desired route. If the first agent won't do it, hang up, try again, etc.

BTW, if you are a 1K/UGS then all award ticket fees are waived.