maintenance works on the swimming pool.

Our pool is open from early May to mid-October.
This year, during the month of April, there are maintenance works to be done and the liner of the pool will be renewed. How can I let possible guests know that they can book but that they should expect a small inconvenience due to the works. How can I let them know that they can get a discount as compensation. I would like them to note this before they actually book