I think submitting rover observations helped speed things up. I have no proof of that, but since they are tight on codes and very busy, it might play into when they get around to it.
I don't think it would hurt to email Gareth and ask, gwilliams@cfa.harvard.edu
if you are interested, there is a facebook group for Minor Planet stuff. https://www.facebook.com/groups/1442958012638876/ they might also have some insight as to what the delays are.
I submitted my required observations in April of 2018, and I got my code in late November. So yah, it could take a while. Don't despair, use the 247 code to submit your observations.
b