Are you changing the lane if you cross the white dashed line in this situation?

In the visible situation, temporary yellow horizontal markings apply, which take precedence over the white markings. The old white lines are crossed out with yellow crosses and no longer define traffic lanes, so crossing them does not constitute a lane change manoeuvre. According to § 85 para. 3 of the Regulation on road signs and signals, if there are both white and yellow signs on the road, the driver is obliged to follow the yellow ones.