Hey there,
Let us clarify without going into specifics for obvious reasons:
Once the patch hits live, each server will be scanned and any overlapping structures will be completely erased from the database. By overlapping, as we explained in the announcement, we mean pieces that occupy the same spot in space. Also, fence foundations in cross formations will be targeted, as that is due to a bug that has been used extensively and caused some troubles.
Once that wipe takes place, servers will restart normally without those targeted pieces in place. That means, that when building stability calculations take place, all those wiped pieces wont be there anymore, thus collapsing any other pieces that would depend on the erased ones to sustain themselves.
As we said in the announcement, those of you who know exactly what it means don’t need any further explanation on what preparations to make before the patch lands. Those of you that still don’t know what all of this mumbojumbo means, it’s almost safe to say you shouldn’t worry too much about it.
And again, this will affect official servers only. It would be very difficult for us to predict the effects of this patch with any combination of mods installed.
As a final clarification, once the patch releases, building this kind of structures won’t be possible anymore.
Hope that cleared it out. Please feel free to share any questions you might have about this keeping our Community Guidelines in mind.