Hi Jake,
Thanks for stopping by planDisney with your question. I wish I could change the weather forecast for you, but my control over the Force is not that strong. I have my fingers crossed that your delay will be minimal, but let's focus on the real possibility that 24 hours before your reservation you realize you will not make it to
Savi's Workshop in time. At that point you should probably cancel your reservation to avoid the cancellation fee.
All hope is not lost. Keep in mind, you are probably not the only one facing delays and cancellations, so you may be able to book a reservation for a different day of your trip as other people have to cancel as well. If that doesn't work, stop by Savi's Workshop or even Guest Relations in Hollywood Studios when you do arrive, explain the situation, and see if there are any openings for the workshop throughout the day.
Make sure that if you are able to score another reservation that you switch any park reservations you may have made for that day to Hollywood Studios.
Hope this helps. May the Force be with you!
Diane