You don't! Next time you record an offering, simply adjust the date, either by typing in the correct date or by using the arrows. You can put a note with your tithe envelopes that tells why that week is missing.
In general, donations should be recorded in the same month the donation was initiated, regardless of when you actually receive the funds. Since the report contains donations that were initiated between September 16 and September 30, the deposit should be recorded in September.
Contributions must be posted in the year they are delivered by the donor. Delivery date is the earlier of:
So yes, post these offerings in December. Then deposit them as soon as possible! When you do your December bank reconciliation, these deposits will simply be accounted for as "Uncleared Deposits". They will then clear when you do your January bank reconciliation.
NOTE: Sometimes people give an offering call on the first Sabbath of the new year, telling the congregation that checks contributed on that day can be credited to the previous year if they are dated no later than December 31. This advice is incorrect and should NOT be given!! Checks "delivered" (as defined above) in January should be posted in January, no matter what the date on the check or the tithe envelope is!
Assuming that the Savings account is recorded in Jewel (it should be!), then the church board isn't quite understanding how Fund Accounting works. Study the How Jewel Works section, and share the information with your board as needed.