Cap 7 shows Mickey & Pete at the Hopewell Cape Community Hall. Hopewell Cape is a town in NB along the Bay of Fundy. This is where the Roadblock and/or Detour take place, (specifically the Hopewell Rocks).
So, my theory is that teams drive from PEI to Shediac (lobster), drive to a DQ somewhere, and go to Hopewell Cape for the RB, DT, and Pit Stop (?).