Need VBA to create new Workbook and name it based on cell value in original file

That's a good question, and yes, you are interpreting that correctly. That said, ideally the Summary tab in Cell C2 would retrieve the earliest "COD" date found in any of the tabs (ending in _CF) in cell C2.

Given that the date found in cell C2 in subsequent tabs will nearly always be greater than said date, I would like the value associated with it to land in the month it is associated.
As an (smaller) example I have provided an attached file. In said file, "Morristown" contains the earliest date found in cell C2 among "*_CF" tabs.
This then finds its way into C2 of the Summary tab. C2 and all subsequent cash flows in the other *_CF tabs obviously occur later than 10/1/19.
The dates that don't fall at the end of a month in these tabs would sum into the month with which they are associated in the summary tab, regardless of them occurring on the 1st.
In the Summary tab of the attached example you'll see that Aldrich and Richland don't become part of the summation until November and December respectively based on their start dates.