Yes, they should plump up a bit. If there remains some dried out crystals inside, you can periodically shake them around a bit and put them back in the recharging station. If they are too far gone, the crystals may be difficult to fully dissolve. If crystals remain, they may not hold the labeled RH. My guess is they would hold a slightly lower RH in that case, but do not know for sure. Haven’t tested that.