I ask a novaexchange what will happen with the coins already list on nova once the change of ownership make
and here is the answer below

Sorry but that is a discussion you have to take to the new owners but it's unlikely
they will not continue with our concept of a lot of different currencies just in a
better more secure way

I do not think we need to panic.
to transfer your currencies on another exchange or a personal wallet the time that it arranges