[Experimental] structure blocks not working over y=255 in experimental mode

While playing in a world created under 1.17.30 with the cliffs and caves experimental mode enabled, structure blocks don't work over Y=255.

I first noticed this under 1.17.30 but still here in 1.17.32.

This might be more a bug with how cliffs and caves experimental mode works than something in the final 1.18 code.  I do not currently have beta access set up.

When I try to "save" a structure at a height above 255 (299 in the attached screenshots), it forces a max elevation of 255 via a -y offset of -44.  If I use corner blocks and "detect" the bounding box it does seem to work but if I tweak the dimensions at all then the forced negative Y offset kicks in.

Similarly if I try to "load" a structure over 255, it will force a -y offset so that the load location is below the 255 height.

It "feels" like I'm tripping over some "helpful" boundary conditions checks that may need an update.

If it matters. I play using a local BDS instance.