Stuck in the Past- Harry Potter Next Generation Time Travel

The huge hourglass in Harry's office was thought to be just a decoration.
But when Fred II and James II accidentally break it, the Next Generation Potters and Weasley's, along with Teddy Lupin and Scorpius Malfoy, are sent back in time.
They are sent to the Golden Trio's Era, to the dawn of the second Wizarding War.
They need to get back, and worse: they have no one to go to.
Will they get back to their time?
Or will they end up stuck in past.... forever