L4 is surely not automatic (at least on INTL). As I do not want all roads locked by me to raise their locks to L4, as that would cause problems to L3 AMs, I haven't asked for L4 yet and I'm L3 still. I will ask for L4 later, when it will make more positive than negative effects.
I still hope devs will implement better locks functions, so segment lock would be adjustable to lower than editor's rank.
if it looks strange, it's my phone's fault