In this situation, when changing the traffic lane, do you have priority over the vehicles moving in the left lane?

Why?

The signs and road markings show that the right-hand lane ends and you need to move left. In this situation, you must give way to vehicles in the left-hand lane because you are changing lanes. A lane ending does not, by itself, give you priority.

art. 22 ust. 4 Prawa o ruchu drogowym