55 Pa. Code § 3042.94 – Parent or caretaker copayment requirements.

(a) If the copayment is decreased as the result of a parent or caretaker voluntarily reporting a change or as the result of a redetermination, the parent or caretaker shall begin paying the reduced copayment on the first day of the service week following the date the parent or caretaker reported a change or the date the redetermination was completed.
(b) If the copayment is increased as the result of a redetermination, the parent or caretaker shall begin paying the increased copayment on the first service day of the week following the expiration of the notification period specified in § 3042.151(a) (relating to general notification requirements) advising the parent or caretaker of the copayment increase.
(c) The copayment is due on the first day of the service week and each week thereafter, regardless of the day the parent or caretaker enrolls the child.

This section cited in 55 Pa. Code § 3042.86 (relating to change reporting and processing).