It's worth remembering that the push towards the south doesn't actually have to reach the Azov - it just needs to get close enough so artillery can interdict convoy travel on the 'land bridge' to Crimea. The Kerch bridge is under regular attack, as are bridges crossing the swampy eastern connection between Crimea and that land bridge.

With both routes out, logistics to the area south of Kherson go to hell and the Ukrainians can focus fire on depots and command centers.

I'm just a non-military person looking at a map, but that whole area north of Crimea looks to be at risk.