Cycle Route sign for Isle of Dogs pointing the wrong way (surely?)

There's an old LCN cycle route signed as 'Hackney' to 'Isle of Dogs', running north-south along Cannon Street Road (actually quite useful, joining Q13, CS2 and CS3). However at the junction with CS3 (Cable Street), there's a sign saying to continue south down the B108 Cannon St Road to get to Isle of Dogs. This can't be right, as all that does is dump cyclists on The Highway (A1203). I think it should point east along CS3 (as the way to reach Isle of Dogs from here is follow CS3, then turn south onto NCN1 (Three Colt Street)