In Maine the US-1 Rockland location is NEVI, and is listed by Efficiency Maine as slated for 2024. (Efficiency Maine removed the Bangor Shell from their NEVI list, so if Rockland weren't going ahead I'd also assume it'd be removed.)
While you'd like a Supercharger before Rockland, if either they include NACS or you have a CCS adapter, the upcoming NEVI chargers Brunswick and Waldoboro should be a significant help. (For Phase VI (2nd NEVI) Efficiency Maine has added language that NACS is strongly encouraged and that the funding will cover NACS connectors.)
I'd also note that in Maine Tesla also doesn't list Bangor (almost ready) or the Augusta expansion/upgrade (NEVI), so no guarantee there isn't something else unlisted.