After spawning oil I sometimes sit while it arms to break LOS. Then I stand and fire the oil. I tried this today and was not able to fire the oil. I kept getting a message that stated "The cauldron of boiling oil is not ready to fire yet!". I was able to reproduce at a keep not under siege.
1) Purchase oil.
2) Sit while the oil arms.
3) When oil shows ready stand and attempt to fire.
4) You get message the oil is not ready.
The only way to fire the oil is to release it by leaving and arm it again and this time do not sit. A video is attached with example.
https://youtu.be/sxl9mwqYsVg
