How do you keep water from getting behind the liner and moving it out of place when you have a lot of rain?

We have a vinyl lined in-ground pool and in the winter, when we have some torrential rains, I go out & open up the backwash valve on our filter & drain the pool until it's at a level where the water won't get behind the liner. Or else I remove the bleed valve located at the top of the filter. Both ways work well. I don't worry too much about recharging the filter with DE filter powder until the rainy season is over. So, depending on where you're located, you may have to recharge your filter after doing this.