Presuming I should not enter the bus lane at any time...
Plan 1. I could stop at A and wait for the back of the queue to start moving, then follow the back of the queue to B and then enter the left lane.
Plan 2. I could stop at B and wait for the back of the queue to move forward to B and then enter the left lane.
Plan 3. I could stop at C and wait for the back of the queue to move forward to C (or jump in if a gap appears earlier).
All 3 feel uncomfortable, especially if there is a car right behind me.
BTW, pretty much everyone else just joins the back of the queue regardless of the fact that they are illegally entering the bus lane.