The case manager must make a reasonable prediction of the amount the household expects to be billed during the certification period for allowable medical, dependent care, and shelter expenses. Anticipation of these expenses is based on the most recent month's bills unless the household is reasonably certain a change will occur. At certification, the household shall report and verify all medical expenses. The household's monthly medical deduction for the certification period shall be based on information reported and verified by the household, and any anticipated changes in the household's medical expenses that can be reasonably expected to occur during the certification period based on available information about the client's medical condition, public or private medical insurance coverage and current verified medical expenses. The household shall not be required to report its medical expenses during the certification period. If the household voluntarily reports a change in medical expenses, the Department shall verify the change in accordance with 106 CMR 366.100: Changes During the Certification Period if the change would increase the household's allotment. Verification of the change in medical expenses is required before the Department acts on the change. In the case of a reported change that would decrease the household's allotment, or make the household ineligible, the Department shall act on the change without requiring verification, though verification which is required by 106 CMR 366.100 shall be obtained prior to the household's recertification.