Hi Pontificator_extraordinaire!

Thank you so much for your detailed explanation.
Here we have modified the lanes tags for the easternmost road segment and middle part (from https://www.openstreetmap.org/node/1518000019 to https://www.openstreetmap.org/node/13120657642).  However, we did not alter the lane tags for the westernmost way. The lane tag of 4 remained unchanged after the split, as this was the original lane count on the initial road https://pewu.github.io/osm-history/#/way/149600048.
We also adhere to the approach that the way should start exactly where the turn lane becomes available. If we were to modify the westernmost way, we would split the start of the turn lanes together, as we did on the easternmost way. But, we did not modify the lane tags for the westernmost way.
I understand why this might confuse you. It's an OSM specific that a new way can form after a split, making it difficult to distinguish which of the new ways had tags modified. It is necessary to compare the data from the initial road with the new one formed after split.

Regarding the middle, we map both_ways solely based on markings or signs. We have not considered using this tag for such middle parts. Thank you for sharing your point of view. I can understand your logic here. We cannot be certain that there are six lanes in unmarked middle section. Perhaps we should consider revisiting our policy. Is there any documentation of similar cases in the OSM wiki or discussions on the forum that you are aware of? We would appreciate it if you could share your insights and rationale regarding this decision.

Best regards,
Yuliya
