Liquibase: runOnChange + rollback

According to Liquibase docs stored procs/triggers etc should be stored separately in a single copy and added to changeset with runOnChange to update them for each change. But what is a recommended way to rollback to the previous change? The only idea that I have is to copy them to a separate folder for each release and add apply operation of this version as a rollback (for example, have sql\procs\current for last version all added to changelog as apply and sql\procs\1.0.0 is a copy of sql\procs\current when we started new 1.0.0 release). Are there any best practices for it? Thanks!