oh right, my bad lol, saw the 2017 and thought that particular update happened 2018 ie just last patch
Edit: ahh was thinking of the new bugfix for mining a 2 wide tunnel and the new message which is what you got.
Edit 2: maybe this fix is interfering with the erupt vein
- Bugfix: Fixed a misleading mining warning text when trying to open a double wide tunnel if the slopes were too steep.
Confusing message used to be: Another tunnel is too close. It would collapse.
Improved message: The mountainside would risk crumbling. You cannot tunnel here.
Solution: Surface mine down to reduce the slopes.