Early in 2020, CMS released a major update to its NCD for uses of NGS testing in cancer patients. The update focused on new rules and coverage for germline risk testing (especially for FDA authorized tests) using NGS - here.
On September 11, 2020, CMS released Transmittal 11837, which provides its MACs with official notice that the new NCD exists and claims processing instructions.
Notoriously, in 2018, CMS issued a transmittal about the original NGS NCD which included some new text that changed the meaning of the NCD released earlier in the year. So far, it doesn't look like any weirdness is going on in CR11837.
The instructions ask MACs to work together for uniform implementation up to such time as CMS may determine shared (mandatory) implementaiton rules are provided.