On March 2, the Montana State Senate passed SB 350. It curtails the means used in 2020 to keep the Green Party off the ballot. Specifically, it says that if voters wish to withdraw their names from a petition to qualify a new party, they must do so no later than the petition deadline.
In 2020, months after the Green Party petition had been certified, Democratic Party activists knocked on the doors of people who had signed the petition, and persuaded them to withdraw their signatures. Thus the Green Party was removed from the ballot in August, even though it had already held its own primary in June and had already nominated candidates.
On March 17, the House Administration Committee passed the bill. Here is the text.