Hours spent training in of themselves are a poor metric of training. Not all training hours are equal. I have also never understood the "3 week build, 1 week easy" model. Seems like a waste of a week. I have always adopted an approach of rest constantly being matched to the load.
Good training must avoid repetition otherwish the training effect will be less because your brains will recognize a certain patern. By making variation in your training the incentives will be bigger. This means variation in length, intensity, intervals, elevation, routes, behind a scooter and also the intensity in each week. In the high volume weeks you must also look at the ratio of rest/load. The low volume week is not meaned to rest. For many it will feel difficult to lower their amount of training. This is a natural feeling because you will get better when you train, though sometimes it is the other way around.