I went to place over a stack of structure blocks tier 4 on a tier 4 void miner with the assembly wand and they all disappeared. Relogged and they were just all gone. Real shame. Something to look into?

Non reproducible.

Will keep an eye out for it happening.

It may have actually placed them under bedrock but I cant check. I forgot to move the void miner block into the air

@Hatter243 Is it your single player save? What version of the mod pack?

No, this was on the offical server for ATM3. So the current version? This happened last night.