Otherwise this broke atomicity; we could fetch/store the ref, then crash, and then not upgrade the next time we tried upgrading. The correct model is: the tree has changed if the new ref is different from the merge deployment.
Otherwise this broke atomicity; we could fetch/store the ref, then crash, and then not upgrade the next time we tried upgrading. The correct model is: the tree has changed if the new ref is different from the merge deployment.