The way it is written, it doesn't seem like there is any limitation on how many times this action can be used (and by how many dreamers) in one turn. But (and this is just my personal opinion), giving all dreamers the chance to place all their progress cards from their hands for free seems too overpowered an effect to me. So I would house-rule it so that this action can be used once for every turn with the the approriate turn suit.
The way it is written, it doesn't seem like there is any limitation on how many times this action can be used (and by how many dreamers) in one turn. But (and this is just my personal opinion), giving all dreamers the chance to place all their progress cards from their hands for free seems too overpowered an effect to me. So I would house-rule it so that this action can be used once for every turn with the the approriate turn suit.