Hi,
https://docs.drone.io/releases/1.0.0-rc.1/#upgrading-important says that:
“There is no automated upgrade path from version 0.8.x to 1.0.0. There were incompatible changes to the database that will require an advanced migration utility. We plan to publish this utility, with instructions, on or before November 16th.”
Have you managed to publish the utility somewhere ?