Update 5.x-rc.md

doc/5.x-rc.md

@@ -67,10 +67,10 @@ git scan branch 5.X master -p -n -T
 git scan branch 5.X master -p
  
 ## Push the branches (preview)
-git scan push -p origin 5.X -n -T
+git scan push -up origin 5.X -n -T
  
 ## Push the branches (for real)
-git scan push -p origin 5.X
+git scan push -up origin 5.X
 ```
 
 Finally, skim the published branches to make sure they match up: