Disposition on Discoloration of Boards post reflow

Hi , During one of NPI trial ,we found that boards ( CEM -1 grade )has got discolored on the masking portion ( and not on the conductors) after reflow .Although it does not impact our Form /Fit and Function characteristics , I would like to get your opinion on the following : 1) What kind of disposition is to be taken ? should it be Go-No-Go ? 2) Is there any standard which gives reference to discoloration of boards disposition . I checked in 610 and it does not gives wrt to the board info. but it surely gives reference of conductors which is not our case study . Please advise . Regards Vikas

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