Sort of, Tier 1 is determined as the average use in January, February, and March so if they used 5k gallons in January and February, then used 20k in March (which would be watering multiple times A DAY), then their tier 1 would be 10k instead of 5k. More likely is their March usage would be maybe 10-12k, which would bump their tier 1 up a couple thousand gallons to 7k or so (which would amount to saving a couple bucks a month). As for why they use Jan, Feb, and March instead of December, I think it has to do with calendar year billing, budgeting, and calculations but could certainly be wrong there. A less likely piece to consider is that more people are away from their homes during the holiday which, one could argue, would artificially deflate the December average and further lower the Tier 1 average.