The major version number of a ruleset version consists of the first two digits of the complete version number. For the ruleset version Alberta:04-01-07, the major version number is 04 and the minor version number is 01.
The Skim operation creates a new major version.
Rules in versions below the major version are not visible to rule resolution. If your ruleset list includes version ALPHA:04-07-15, no rules in ALPHA:03-XX-XX are available to you.
Ordinarily, you do not need to create a major version other than the first one — 01 — by using the New function and the rule form. Instead, use the Skim function, which creates a new major version automatically.