It's a Wednesday flight. Security will probably take no more than 30 minutes. If you have to go to "B" it's a long walk to get to the tunnel and the tunnel itself is fairly long. Be advised, the gate agents will try to close the jetway door 8 minutes before pushback time. That's their goal on every flight. That 90 minutes will give you extra time even if you have to go to the furthest B gate.