Split miles (?)
 

I am following a double century training plan, in training for a 24-hour race in Feb.

My question is, can I split my miles into a couple sessions, and still get the same benefit? I commute, so if I ride 15 miles, and then 25 (8 hours later), how does that compare to 40 straight through?

Even on the weekends, I would like to ride the club rides, and hang out for an hour with the club before finishing up my miles. But, I worry that I am not getting the full benefit of the time spent on the bike. Opinions?