When saving as new, I want to break links including sumifs but I'm having an issue

I have a sheet that's linked into a pivot sheet via a series of sumif cross sheet formulae. This sheet is looking into the pivot sheet at a point in time e.g. month of April YTD information, and the Pivot will update monthly as new data is uploaded to the source report (I will also need the new data but the historical data is needed for comparative purposes). I don't want my April YTD sheet to update further, so I tried to save it as new and broke the links but it caused invalid refs on the sumif formula lines.

Is there anyway to break the formula so that it leaves me with the result of the sumif, but as a static number? I'm essentially looking for the same effect as if I had an excel workbook end broke external links.