In the presented situation, are you exiting a road with priority if you turn left behind the visible sign?

In the video you are driving along a street in a housing estate with blocks of flats and approaching a junction at which the road turns left; on the right there is sign D-1 "priority road" with plate T-6a, on which the thick line of the priority road bends to the left and the thin one runs straight on; lower down there is sign B-5 with a plate. When you go left beyond the visible sign, you will not leave the priority road. The answer is: no.

The Regulation on road signs and signals states that sign D-1 marks the beginning or continuation of a priority road, and plate T-6a placed under it shows the actual course of this road through the junction: the thick line is the priority road, the thin lines are minor roads. Since the thick line bends to the left, when you go left you stay on the priority road; it is the driver going straight on who leaves it and enters a minor road. Such a "turn" is not an ordinary left turn in relation to vehicles from the opposite direction, because they are coming along a minor road and give way to you - however, the Road Traffic Act requires you to signal the change of direction with your indicator and to exercise particular caution. That is why you always read plate T-6a, and not only the sign above it.

Legal basis: § 43 para. 1 and 2 of the Regulation on road signs and signals; Art. 22 para. 2 point 2 and para. 5 of the Road Traffic Act (Prawo o ruchu drogowym)