This may be a dumb question but I am a little confused about this. Do you sign a marriage certificate with your current name or your new name?
Also, if you sign the marriage certificate in your new name (which is legally binding), but haven't changed your official documents yet, do (can) you start to assume your new name immediately (e.g. at work/ work email etc) or do you use your old name until you officially synchronize at least your main IDs (SSN/ DL)?
Someone asked me this question recently and I didn't have an answer either so I am curious to hear the responses.