Jump to phase allows an administrator (or a user with jump to phase global permissions) to move a work type from one phase to another that is not usually permitted based on the phase plan configuration. This is often used if there has been in a issue with the system or if a user has mistakenly changed a phase. Typically the user is asked to enter a reason as to why the phase change is occurring.

Feature Configuration
Access this global feature at Launchpad > Admin > Features > Global Features. Search for jump.
When enabled this feature allows the jump to phase functionality to be used across the application. Only users with the 'jump to phase' global permissions can perform this action.

Option Sets
The jump to phase reason will be used to determine the global default list of reasons when performing a phase jump.
Jump to Phase Work Type Configuration
Work type configuration allows the jump to phase to be enabled for individual work types. If this is not enabled for your work type, even with the jump to phase global permission, you will not be able to use the jump to phase functionality.
You can enable jump to phase on a work type and set a specific set of reason codes for that work type.