In a public post on our forum, t!n0 has shared an update on the MSI non-K overclocking BIOSes. In the updated list contains primarily fixed BIOSes for the Krait and Tomahawk models as well as new entries for the Gaming Pro Carbon, the Krait Gaming R6 Siege and the Krait Gaming 3X models. In total MSI has now non-K OC support for 18 Z170 motherboard models.
You can find the full list of supported motherboard models as well as the link to the OneDrive BIOS archive here. Happy overclocking!