"Only person in this conference" call?

Factual Questions
1

I have two landlines – one for my business and one personal. Despite having listed it on the Do Not Call registry, I get a lot of junk calls on the business line.

I just got a call on my business line from a local number that I did not recognize. Caller ID listed it as Wireless Caller. Despite it being Saturday, I answered. A voice told me, “Currently you are the only person in this conference.” Then there was silence. After a few seconds I hung up.

Since conference calls often start out like this, I’m wondering if this was a screw-up (I haven’t been invited for any conference calls in months), or a spam call. If a spam call, what was the point?

2

WebEx has a thing where if you log in to a meeting, you can have it call either your desk phone, or a different # which you type in. Sounds like someone typed in your number by mistake, and was the first one to log in to the meeting.

3

Easily a wrong number for a conference call. A spammer or anyone might be using a computer phone that responds that way if you answer and he has hung up. The spammer may have found some convenient way of using a conference feature to get multiple calls started and then jumps on the first answer leaving you alone in a conference. Even if it’s a spammer it could easily be a mistake.