No-Clean flux residue from Secondary Ops

New pcba supplier sent us first article pcbas (SMT, Wave & hand solder operations) that failed our testing due to no-clean flux residues found under ICs and around passive capacitors. Second lot came in and had 100% pass yield, but we still see a clear residue around IC and caps due to secondary hand solder operation. What is long term risk of this residue? We have done some HALT testing (via humidity testing) with no negative results, but are concerned about long term failures that may result from the residue.

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