I think all ANCs have monthly meetings. If you attend these (and fair warning, they can be quite painful to attend), they should discuss changes to streets/traffic patterns, including reps from DDOT discussing changes.

These meetings are listen-only (unless you've been approved to speak ahead of time), so it won't help if you want to share feedback, but it is useful to see what's coming down the pipeline.

If you're on Twitter, you may be able to find local residents who live tweet these events. I would start by following your local ANC rep and the algorithm should do the rest.