Does the visible sign in the situation presented, warn drivers travelling on a one-way road of approaching a point where a two-way road begins?

In the video you are driving on the one-way roadway of a dual carriageway, with a barrier on the left and a strip of grass; on both sides of the roadway there are yellow triangles with two arrows pointing in opposite directions - signs A-20 "section of roadway with two-way traffic". They warn drivers travelling on a one-way roadway of the place where two-way traffic begins. The answer is: yes.

The Regulation on road signs and signals states that sign A-20 "section of roadway with two-way traffic" warns drivers travelling on a one-way roadway of the place where two-way traffic begins; a sign placed on the left side of the roadway repeats the sign on the right side. You will most often meet this situation on a dual carriageway under repair: when one carriageway is closed, its traffic is moved to the other one, and suddenly, on a roadway where until now everyone was travelling in the same direction, cars appear from the opposite direction. A driver who is not aware of this may move into the left lane straight into the path of an oncoming vehicle. Beyond sign A-20 you keep to the right, you do not overtake without making sure that the left lane is not intended for traffic in the opposite direction, and you pay attention to road markings - yellow lines mean a temporary traffic arrangement.

Legal basis: § 10 para. 2, § 2 para. 1, § 3 para. 1 and § 85 para. 3 of the Regulation on road signs and signals