glad you found the solution to problem #1.
Issue #2 is a bit more mysterious to me. I'm not aware that/how the stored proc could suddenly use more memory in the server. The only idea I have at the moment is that there is a code path or configuration that pushed the right type of parameters in the past, but now uses something else; this in turn would let the server execute with a different execution plan which then could have different memory characteristics.
I have seen such behavior in the past when by mistake a NVARCHAR column was used with a VARCHAR parameter and suddenly the defined index was no longer used....
As you are calling a stored proc, this also rules out the possibility that a different SQL was generated.
Could you perform a server side analysis to check the difference between old and new assemblies?
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