OK guys, got a bit of a dilemma. I got myself a new iPhone 8, I've been testing it and taking photos for the past month before switching everything over. I registered a new iCloud account for the iPhone 8. So now I've got over 2k photos on the new phone. Question is if I just switch the iCloud account on the iPhone 8 to my old iCloud account, do all my new photos remain or do they get deleted?