Saint John would be good.
Woodstock, when it opens though, will get you to Moncton from either brewer OR rivière du loup. So I don't expect Saint John any time soon because, as a route to Moncton, it would require you to use the slower Maine highway 9. (Which I prefer but I doubt many other people want the slow road instead of the interstate.) For those brave enough (like me) you can already drive from Moncton to brewer Maine in a 75D on a full charge--at least in the summer, if you drive slowly enough.
And if Saint John is your actual destination you can already get there from brewer, and prob from Woodstock.
Beyond Moncton, NS is a very different problem. You need a station at Truro but also two in the south and at least two up north because the province has a sort of "figure 8" highway structure with the middle point at Truro. You can't get around the Cabot trail on one charge, even if it's at the canso causeway. Similarly you can't get from Halifax around the south shore and back. So likely we need at least 6 chargers in NS to do the trick and that's a hard sell for a small province. My fingers are crossed though because I'm from NS.