The electronic version is updated as soon as "new light" comes out.
For instance, when they changed the definition of "faithful and discreet slave" from "all anointed JWs on earth at any one time" to "8 guys in a lakeside corporate compound in upstate New York" a few years back, the electronic version of that topic in the "Insight" volumes were updated just a few weeks later.
So, if you are reading the Insight book from any jw.borg site, it might have been updated a month ago, a week ago, or 5 minutes ago.