There is nothing in party rules that allows such exclusion. Some insiders point to the preamble to party rules which states: "Devotion to our Party’s principles and loyalty to its candidates are and should be the only qualifications for holding any position in the Republican Party."
If that is what the establishment types are hanging their hat on to start kicking people out of the party, they are doing it arbitrarily. Repairing selective application of this "rule" would require expulsion of the entire GOP state Executive Committee, which voted in 2010 to not support the Republican nominee in the state Senate's 2nd district. If there is a specific statute of limitations on this imaginary "loyalty clause," it should be specified immediately. Otherwise, we might wonder if it applies to the state Senate President. A Republican, he supported Democratic Governor Paul Patton's re-election in 1999.
If you don't support such shenanigans used to personally attack fellow Republicans despite (and arguably because of "devotion to our Party's principles", you just might be a Red Star Republican.