The winter plan followed by the 100 miler plan is a great combo.
Commuting can fit into the plan. Where possible count your commuting miles as training. Some days the training calls for an easy 90 min ride. Other days you could do your workout during the commute.
Another option is to commute only once per day. Drive to work with your bike, ride home that day, ride in to work the following day and drive home at the end of the day. I have several athletes follow that sequence twice per week. You can fill your car with a cooler containing healthy food and clean clothes to access at work.
Lynda