Hidden orders in ES options

I just went .65 bid on the 1350 puts and traded immediately even though the market was .70 offered. Why is this?

 

You were the NBBO and a trade came through that the specialist was required to execute at your price.

 

I thought it was electronic?

 

There is no specialist on ES options, they're options on the futures its a different system. Same with NBBO since they're the only market. Most likely your screens were slow when the market was whipping around