New tugboat engineer with some questions

I just recently graduated from Schuyler and was just employed with a well respected tugboat company. When I joined my crew, the Captain and the Mate as well as the Deckhand kept calling me “Chief.” I wondered why, then did some research and found that engineers that serve on smaller vessels that do not have oilers or wipers are referred to as chief since I do all of the jobs. I did some more research and found a correlation between 2 A/E’s and C/E (limited) license wise.

My question is, does anyone know for sure if and when I do upgrade my license to 2 A/E, do I automatically get my Chief engineers limited endorsement? If yes, does this mean higher pay possibly?

Another question that I have, my vessel that I am on now is rated at 4200 HP, is this enough for the raise in grade from my 3 A/E to 2 A/E after I get enough sea time?

Thanks everyone for any feedback.