During the armored car robbery, we see that Neil's crew uses police scanners to determine the response time. But in the bank robbery, one wonders why, if Breedan had a police scanner in the getaway car, why didn't he pick up on Hanna organizing the roadblock via walkie talkie? Well, you have to think about the evidence that was left behind during the armored car robbery: during the forensics investigation into that crime, the police probably found pieces of melted plastic later identified by forensics as police scanners in the burnt-out ambulance, and even if they didn't, Hanna assumed from the beginning the crew was using police scanners given how he observed at the scene of the armored car robbery how well prepared and technically adroit the crew had proven to be (in the sense of them knowing how long they had until the first squad car arrived), and likely, figured that they'd be using police scanners if they carried out any other jobs.
Therefore, at the bank robbery, Hanna would have used encrypted frequencies within his team, and possibly employed cell phones, to contact the patrol units (in addition to just grabbing whatever uniformed officers at headquarters that he could find when the information came in) without tipping off Neil's crew. Once the shootout begins, the dispatcher's center is undoubtedly flooded with 911 calls from bystanders as well as uniforms on the scene requesting backup, leaving Neil's crew no choice but to quickly blast their way out before the essentially endless stream of police reinforcements overwhelm them (we see that backup only begins to arrive as Hanna chases Neil and the wounded Shiherlis into the parking lot).
Neil's words he lives by come back to haunt him at the end, but it still only takes him 29.8 seconds to walk out on Eady.
