This is that "weird" rule.
https://casetext.com/analysis/legislatu ... onversionsChapter 11.5 of the California General Corporation Law currently authorizes the conversion of a corporation into an "domestic other business entity" (defined in section 167.7) such as a limited liability company or a partnership. While a "foreign other business entity" (defined in section 171.07) may be converted into a "corporation" (generally, a corporation organized under the GCL), the GCL does not presently authorize the direct conversion of a "corporation" into a foreign corporation (defined section 171) or a "foreign other business entity". Nonetheless, such conversions were not impossible as corporations could achieve the result by first converting into a California limited liability company and then converting into a "foreign other business entity" pursuant to Corporations Code Section 17710.02.
But see that last sentence..
So we convert the CA Corp to a CA LLC, then we convert to a MT LLC. Voila! Taxpayer has a MT LLC (taxed as corp) with the same EIN.