Perhaps there could be a data contribution network, a bit like the "tell us where you've seen a butterfly/Asian wasp" ones.
People can self-ID as either a Red Counting Person or a Non-Red Counting Person and then send their data in for the count that day. Thus building up a picture across the whole year of the baseline Red vs Non-Red ratio.... ready for the grand reveal at the end of 10th October next year.
Obviously we could have a situation where TRAs skew the figures by wearing red on every day except the 10th October, so it's not entirely foolproof. Given the effort involved in that, not to mention the impact on their wardrobe/laundry (you've either got to buy lots more red things or constantly wash the ones you've got to sustain it), they're more likely to try other forms of protest instead. It's far easier to demonstrate contempt for a group of people by releasing a swarm of crickets in to an event that they're running, for example (see reason demonstration at an LGB conference to illustrate how quick and easy this is to do).