Usage help text should inform about plans with end dates beyond agreement date

**As a** *(User Type/Persona)* **I want** *(Feature/enhancement)* **So That** *(Value, why is this wanted, what is the user trying to accomplish)*
As a user, if i update the plan end date to be beyond the agreement dates, the usage will update on save. The help text for usage should inform me that this is the behaviour.

**Additional Context**
- Current help text:

- Suggested: (@LisaMoore1 can weigh in here):
"Authorized usage entered in FTA. For plans with end dates currently beyond FTA agreement end dates, the MyRange usage will carry forward based on the last year entered in FTA, but only once you hit Save. If otherwise incorrect or incomplete, update FTA and wait for daily synch of MyRangeBC with FTA. "

**Acceptance Criteria**
- [ ] Hover over usage ? icon and get new help text