Variable linkage to billing for expiration date for treatments and packages

[astaclinicbot]

The current behavior of the system do not allow for billing / invoice adjustment for the expiration field when issued from a treatment or package, we would like the flexibility to update the billing record on the expiration date of a treatment or package when its expiration is updated to reflect on subsequent visit by the patients

[astaclinicbot]

and also we would like the existing issued bills to have the ability for us to modify the set expiration date to avoid confusion during patients' next visit, thanks