The fine manual says this about replacing an encrypted drive
This is seriously scary. Resilvering is a process which lasts multiple hours on a nontrivial install. It is possibly the most work the NAS has ever done, so possibility of crash is real (if only because of thermal issues).
Can you restore the encryption keys just after resilvering has started? Is it dangerous? What will actually happen if the NAS crashes during resilvering?
Wait until the resilvering is complete. Next, restore the encryption keys to the pool.
This is seriously scary. Resilvering is a process which lasts multiple hours on a nontrivial install. It is possibly the most work the NAS has ever done, so possibility of crash is real (if only because of thermal issues).
Can you restore the encryption keys just after resilvering has started? Is it dangerous? What will actually happen if the NAS crashes during resilvering?