I also received both emails (the "unauthorized access" and TSA opt-in). I did link with my US Air account over the weekend, but it sounds like from the other emails that is not the issue here. For what it's worth, I linked from the US account (i.e. logged into the US Air website with that number, then entered the Aadvantage number when requested to link). Just talked to the EXP desk who had no info at all and said we need to call back tomorrow when customer service comes on. So, just adding another data point.