Timing is everything in most of the preps and defensive action/reaction that need to be taken. The transition time between the event (let’s use a cyber grid down event) and total lawlessness might be a few days. If a person or group blocks public access to roads I expect the local LE will not be happy with this action. After a few days they may want the protection for themselves, but at first it’s going to pose a problem. Dealing with the first trespassers will also present a challenge.