[Goose]

I assumed (perhaps incorrectly) that the P66 is close enough to Ukrainian territory that Ukraine can scout it with drones and hit any convoys with artillery.

BC

You are certainly correct that Ukraine has the P66 under their artillery footprint at least near Kreminna. However, as the Russian retreat from Kherson demonstrated, having a road under fire doesn't mean you have shut it down. There is a cost to use it, but that cost may be low enough for it to still make sense. It is also a problem for Ukraine to commit artillery to closing the P66 as a primary task. They need it elsewhere too. You also need it to be available 24/7 as do the drones. The ammunition for the guns needs to be brought in without the benefit of an obvious road. On top of that, you have the problem of moving your guns around to defeat counter-battery while still maintaining fire control over the road. It is just a heck of a lot easier if you are sitting on the road with infantry. It is also obviously necessary if you want to advance across the road and into the lands beyond it.

[Goose]

I assumed (perhaps incorrectly) that the P66 is close enough to Ukrainian territory that Ukraine can scout it with drones and hit any convoys with artillery.

BC

You are certainly correct that Ukraine has the P66 under their artillery footprint at least near Kreminna. However, as the Russian retreat from Kherson demonstrated, having a road under fire doesn't mean you have shut it down. There is a cost to use it, but that cost may be low enough for it to still make sense. It is also a problem for Ukraine to commit artillery to closing the P66 as a primary task. They need it elsewhere too. You also need it to be available 24/7 as do the drones. The ammunition for the guns needs to be brought in without the benefit of an obvious road. On top of that, you have the problem of moving your guns around to defeat counter-battery while still maintaining fire control over the road. It is just a heck of a lot easier if you are sitting on the road with infantry. It is also obviously necessary if you want to advance across the road and into the lands beyond it.