I use a simple strategy.Continue mining even at a loss if I am financially stable to afford it as I believe that the prices of almost all cryptocurrencies,at least the ones who will make it and will not die like many alt did in the past is that their prices will only keep increasing in the future.
The better strategy for people who own rigs is to not rush and sell their rigs,rather keep mining until the PoS thing happen,if it happens at all and then after the merge see if there are other coins which can give you decent profit (do not rush,the difficulty will decrease a lot when people will rush to sell their GPU-s) and if there are keep mining them,you need about 2-3 months after the merge to see the exact picture,so the real winners will be the ones who will be patient enough to resist the strong urge to sell gear.