Do Crest Whitestrips need to be used in close succession...?

It’s June, which means it’s time for my annual round of Crest Whitestrips. Well, they are hurting my bottom row of teeth. Pain starts 2-3 minutes after I put a strip on, stops as soon as I take it off. I guess it’s a gum thing (I have never had a cavity… what do they feel like?) It makes sense that it would be a gum thing, because I’ve just been on a very stressful trip, and in the past, stress has made them inflamed.

But none of this is my question (hooray! no medical disclaimers needed!) What I want to know is: if I discontinue the strips for a week or so, then start them again, will I end up with the same whitening in the end? Is there something about them that makes them work better when used twice a day for seven days, as directed? Or is it all strictly cumulative?