Thoroughly explain Teslas use of regulatory credits to log revenue and offset operating costs. Is Tesla able to choose in which quarters these credits are recognized?

ZEV credits (ZEV=zero emission vehicle) are awarded to car makers who sell electric or hydrogen cell powered cars in certain participating states. Each car earns differing levels of credit based on the range of the vehicle and certain characteristics such as if the vehicle is purely electric or a hybrid gas/electric car. In the states that participate in this program, car makers are required to earn, or purchase on the market, a certain number of ZEV credits relative to the number of cars they sell in that state.