VBA to change a value and save a result sheet as PDF with value as name

Hi,

Could you please assist me with the following:
In a workbook, I want the macro to change the value of a cell according to a list on a different sheet, while that value is valid (has an associated entry greater than 0)
Once the value has been changed, let it finish calculating and then save a third sheet as a PDF, naming it according to the value + the previous month's date.

Example workbook with comments and details attached

Thanks in advance

P.S. If it can also email the resulting pdf to the email entry that'd be great, but that's just a bonus, not a necessity