Technically the peak is the peak (except when it’s not… more on that later). I see you’re signed up for the Bay Area challenge. One thing to keep in mind is that while we do have recommendations on the route to the summit, those are suggestions. You can take whatever route you want to the summit, including a shorter route. We rely on the honor system, and ask that the hike be a challenge to you. For some people, a 20 mile hike falls into the too hard category. Take a look at some of the other peaks and consider selecting alternatives from the list.
Some of the peaks in the Bay Area challenge, like Mount Diablo and Mount Tam, have many routes to the summit. Consider taking a route that starts five miles from the summit if 10 miles is your limit. Over time, you might find you can stretch that limit to 12 miles or even more.
You are fortunate in the Bay Area, in that you can hike right up through December 31st without worrying about snow. If you’d like help coming up with a game plan, let me know and I’ll give you more specific suggestions.
As for the question of when a peak is not a peak. Some of the other challenges (not the Bay Area) include mountains where the “peak” isn’t actually the top of the mountain. For example, in the Arizona Winter challenge, Flatiron is an iconic geographic feature, but not a true “peak” but that is the destination for one of the hikes. There are a few other similar examples out there in some of the challenges. 😉