The law is in effect now. Certain data collection and reporting aspects and a couple other bits take effect later, but the parts that govern use of force, civil and criminal liability and POST de-certification are in effect. This is a state law, not a Denver or Aurora thing. It is possible the rural areas and smaller cities have not paid as much attention, but EVERY local law enforcement agency and officer, deputy, etc. is subject to this law, and any agency that does not update its policies to conform is setting its officers up for a disaster.
Realistically, when a cop has several years on the job, state certification, owns a home, his kids have friends, his wife has a job, etc., just packing up and moving away to start over in some other state is not a minor thing.
I received a copy of the first draft of the bill within a couple hours of it being introduced and assigned a number. This particular law was not a bi-partisan effort, but some politicians who might otherwise oppose it were reluctant to risk the public/political backlash. Some of the worst bits from the early drafts were actually toned down in the final version. This legislation was rushed through in response to the Floyd and related situations last year. It took only six days to make through both houses and committees and six more days to be signed by the Governor, and the signing delay was only so he could sign it on Juneteenth.
I will say no more about the politics of the the thing. If anyone is interested in the political side of this, look up the bill to see the sponsors, their backgrounds and other pertinent info. It is all public record. One of them even has an article on her webpage in which she expresses her pleasure that over 200 cops have left the job since the law was passed.