There is mound north of Svitle, they could be just waiting to tight the noose? I've seen more than a few tall buildings (SE) in Bilitske, but I don't know what kind of "preparation" it has suffered.
The town is basically destroyed. There's plenty of standing buildings, but it's been hit hard for quite some time. In general any town that spends a substantial amount of time on the front lines ends up destroyed in this war. The ones that come through more or less intact are ones where Russia manages to take them relatively quickly, like Selidovo or Kurakhovo. Even Dobropol'ye is slowly getting wrecked. Neither is at the state Artemovsk/Bakhmut was at, or Toretsk is at, but neither is a functioning urban locale in any way and would require substantial reconstruction.
Biletskoe has quite a few mid-rise apartments, and is generally fairly dense, even more so than Rodinskoe. Maybe Russia will make a play for the refuse mound that you mentioned, but so far they haven't even consolidated inside Noviy Donbas. I guess we'll see. Control of that refuse mound would cut Biletskoe off from Dobropol'ye, and would even compromise some Ukrainian positions towards Dobropol'ye, so it would be a good position for Russian forces to aim for. But there's not much cover on it, and there's a mine complex under Ukrainian control east of it and south of it, meaning it might be hard to hold.
EDIT: Just took a look at AMK's map and he has Russian forces with a foothold in southern Biletskoe, where Suriyak has the grey zone. He also has Russian controlling the mine complex west of Rodinskoe, again where Suriyak has a grey zone. I suspect they're interpreting the same underlying information slightly differently.