In elections there is normally a set of rules for running the election and those rules are either consistent from vote to vote, or there is a clear process for changing the rules.
In the summer of 2022, the Conservative party held a leadership election. One of the rules was that "candidates needed the nominations of 20 Conservative MPs" (source) to enter the first round, and 30 votes to proceed to the second. (This was apparently to rapidly eliminate candidates with very little support in the Parliamentary party.
In October, in a second leadership election, 100 nominations are required, a substantial barrier which may well result in only one candidate and a "coronation". It may eliminate the party membership from a role in the selection of a leader. (source) Had the July election been run under October rules, there would have been no candidates at all!
By comparison, in 2019, only 8 nominating MPs were required.
How was the rule changed? How much could the rules governing the election of a leader be changed?