Your method looks good. One of the better time-lapse stories I've read is
Safe by Oboko-chan. (This is an Ouran High School Host Club story, rated M on FF.N, but I think MA here.)
The time switches in that story are done the way that you propose, with just a basic break between them. If the writing is well done, there's no need to indicate at the beginning of each section when it is taking place, unless the specific date and/or time is important to the plot. And if the writing isn't well done, all those "Flashback" or "Past/Present" titles can still be really annoying (personal opinion, I'm sure some people love 'em).