It seems that your I-612 takes longer than usual time to process.
It is generally ture that you can extend your J-1 before a favorable recommendation letter is issued by DOS. However, DOS officers need to have all your I-AP66s at handy in order to avoid trouble. Otherwise you may need another waiver. However, the enforcement of this rule is up to the CIS. And in the past the rule is not enforced strictly. At this point, I am not sure if the extension delays the processing. Now that the I-612 is transfered to TSC, wait a month before you make another inquiry.
It is generally ture that you can extend your J-1 before a favorable recommendation letter is issued by DOS. However, DOS officers need to have all your I-AP66s at handy in order to avoid trouble. Otherwise you may need another waiver. However, the enforcement of this rule is up to the CIS. And in the past the rule is not enforced strictly. At this point, I am not sure if the extension delays the processing. Now that the I-612 is transfered to TSC, wait a month before you make another inquiry.