I am having sinkholes fixed in the bottom of my above ground pool. The repairman has asked me to drain the pool before he arrives. The liner is only a year old. How long can I leave the pool empty without damaging the liner?

Draining is no big problem but I seriously doubt that you can reuse the liner. You must drain the entire pool and remove the liner for the repairs to be done. As soon as the liner is out of the water it will shrink a small amount and it is also slightly brittle compared to when it was new. I have never satisfactorily reinstalled a used liner. A liner is only around $300 and the work involved to install a new one is excatly the same.