@Starryk. Don't think so, some weeks they hide the cards. More frequently than not they show them in advance, as far as i can tell.
The pictures are not intended as a preview anyway, they are discovered by the unstoppable necessity to unveil mysteries of some users, or those who can't wait. I don't see a company policy here, maybe the pictures are available once the team or the boss decide which cards will be released. Guess they make up their minds earlier some weeks. Just speculating here.
Nonetheless, this is guesses for the new releases, so i'll guess.
A Bianca card is overdue, so i'll bet on her. There are cards on beta test at 640 and 646 spots, so a new model is a good possibility. There are cards on beta test matching Krystel and Ting spots, so maybe one of those could be the third and sort of a counter-strike measure. Finally, with all the new models coming fast, it won't be a surprise if Nicca's cycle ends next friday.
Cheers. ;)