MM to BB as AN2, how to actually perform well once you're in?

Making the jump from a MM bank to a top coverage group at a BB (GS/JPM/MS) as an Analyst 2. Plenty of threads on how to get the offer, but not much on what actually matters once you're sitting at the new desk.

A few things I'm trying to get ahead of (not exhaustive list):

Technical/process gaps: what tends to trip up MM analysts moving to a BB — different modeling conventions, deal cadence, comp/format norms, deal team structure, etc.?

Ramp-up expectations: is there any grace period for a lateral analyst, or are you expected to be plug-and-play from day one given you're coming in mid-level rather than as a new grad?

Reading the room: culture/politics differences between MM and BB that caught you off guard — pace, hierarchy, how MDs expect to be communicated with, analyst dynamics, etc.

Building credibility fast: how did you prove yourself to a new team who didn't watch you come up, especially without the built-in trust that comes from being homegrown?

Would love to hear what surprised you in the first 3-6 months and what you wish you'd known going in. Thanks