If there are males and females in the same tank, then the females will spend the rest of their lives (pretty much) pregnant. Having looked at the photos, I'd say they still had a fair while to go before their next drop.
One thing to point out, though, is that unless you manage to develop a very unique colour morph, you will probably find it difficult to move on the fry. Common livebearers are so cheap for the LFSs to buy, from their trusted sources, they tend not to want to take fry from a stranger, whose history they don't know, and who might be introducing disease into their tanks. Just something to think about.
Have read of this link here, it's an excellent reference piece that applies to all common livebearers.
+1 The Lock Man, If there are males your females will always be pregnant, and from my own experience it's so difficult to "get rid" of the fry once a new batch comes. You may find you get quickly over run with guppies and it could become a problem when juveniles start breeding with juveniles and so on...
Also, you can see the females gravid spot in the photo, but they've probably got a couple of weeks to go until they're squared off and ready to drop. You've just got to be prepared for 10-50 fry, from each female every 28 days ;D