You may be correct, but just a side note I have been speaking with my FSDO about the topic of this thread and they keep agreeing with me regarding 61.159. As far as the ATP written goes, if you have a current 121 ATP passing grade it will remain current so long as you have been engaged in 121 operations. That said, the ATP written will be current when you go for your exam. To err on the side of caution, it was recommended to me to get in contact with the examiner you will be using for your check ride, apparently they have a lot of discretion in the matter, i.e., whether or not they will accept your SIC time or not. I am not telling you that you will or will not have to re-take your written, but simply to get in touch with your examiner because at the end of the day they are the one who will sign your 8710. If your examiner says you don't have to re-take it and he'll accept your SIC then you're good. Call your examiner.