On 8.6.2014 I received a call from this number, too. No caller ID. I did not answer and no message was left. Interestingly, I had recently been on the phone with Blue Cross/Blue Shield, as "scamfighter" stated the caller represented themselves, when spoken with.
Like the others, I was on the phone will BlueCross BlueShield of TX, yesterday. I signed up for their "case manager" thing. It does seem strange that phone calls start the day after...
What is the app you have to block calls. Sounds like a great thing to have. I didn't answer my call because I don't if I don't recognize the number or there's no ID with it.