My weigh in was just approved and is still called a progress weigh in. I think the rule is for it to be within 48 hours. On the last day in January, they asked me if I wanted my progress weigh-in to be my final. I said yes and it got accepted.
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The final weigh-in window for this game is March 10-11 (Pacific Time). If you have an approved weigh-in that was submitted within 48 hours of that time, you should be able to re-use it. You just need to initiate the weigh-in process as you normally would and you will be prompted to re-use your approved weigh-in.