Ardoyne parade: Police ready to act, but hope they won't have to
The PSNI's full public order capability has been mobilised for the Twelfth demonstrations.
There is also a contingency to more than double that capacity within 24-36 hours if needed with mutual aid or support from other UK forces.
But that's not Plan A for tomorrow, rather a worst case scenario.
"We don't want to show our teeth unless we have to," a senior police source said.
If you look at it in numbers terms, the PSNI has around 50-60 public order units. Each of those units is 25-strong, with usually an inspector, four sergeants and 20 constables. With each unit there are five Land Rovers. Water cannon and dog teams are also part of the capacity.
Add it up and you get some idea of the numbers.
But, tomorrow, the police don't want to go toe-to-toe with marchers. They have heard the calls for peaceful protest and hope they are also heard on the ground. And the quieter things are, the softer the policing profile can be.
Last Twelfth at Woodvale the police had to put in a solid line of vehicles and officers to hold back a violent crowd. But, just a few weeks ago, they were able to stretch a metal barrier across the road at the same point. Tomorrow, that would be preferred option.
Part of the "graduated response" is for evening parades across the many Orange Order districts. Many already happen as a matter of course and notice has already been given but, at the eleventh hour, the system could be clogged by fresh applications. Those forms go to the police first and then to the Parades Commission – it really can be a last minute affair.