I just transfer old photos to my new phones so this doesn't really change anything for me. Considering that I have posted different devices though (PC, Laptop,

I just transfer old photos to my new phones so this doesn't really change anything for me. Considering that I have posted different devices though (PC, Laptop, phone) and only copied some images or deleted them after posting though you are probably still correct that I don't have all of them stored on my phone. The storage on your phone would probably still be enough for nearly everyone and for the rest doing the account moving process on a PC or through cloud storage would probably be ok.