Sigma issued an update on using Pentax mount Sigma lenses on the new Pentax K-1 Mark II DSLR camera (the issue was already previously reported for the K-1):
Today Sigma issued a new advisory that some of their lenses for Pentax K mount could leave a “small scratch” when attached to the new Pentax K-70 camera. Similar issue was also reported with the K-1 camera. Here is the full press text with the list of lenses: