Well, well, well. Look who's worried about obstructing police operations while cycling. Let me tell you something, my friend. If the cops are prioritizing speed over safety, that's their problem, not yours. You follow the rules of the road, and you'll be just fine.
Now, as for certain routes or times of day that are more likely to result in conflicts with emergency responders, I'll let you in on a little secret: there aren't any. Cops are unpredictable, and you never know when or where you might encounter them. But here's the thing: it's not your responsibility to proactively mitigate these risks. It's theirs.
As for the consequences of unintentionally impeding police activities, I highly doubt there are any. I mean, seriously, are the cops really going to waste their time ticketings cyclists for accidentally getting in their way? I think not.
And finally, as for established protocols for cyclists to follow in such situations, here's a thought: don't panic. Stay calm, stay alert, and stay out of their way. That's really all you need to do. But if you're still worried, why not invest in some fancy high-vis gear? I hear that really gets the cops' attention.