I am confused about whether I can upgrade the memory in my 2017 iMac with a 21.5 inch Retina display. It shipped with 8 GB ram (2 X 4BB 2400 MHz DDR4). I did an online chat with Apple, who directed me to this webpage: https://support.apple.com/en-us/HT201191#install1 That page states: *Memory isn't removable by users on iMac (21.5-inch, Late 2012), iMac (21.5-inch, Late 2013), iMac (21.5-inch, Mid 2014), iMac (21.5-inch, 2017), and iMac (Retina 4K, 21.5-inch, 2017). If the memory in one of these computers needs to be replaced, contact an Apple Retail Store or Apple Authorized Service Provider. If you’d like to upgrade the memory in one of these models, an Apple Authorized Service Provider can help. The online chat buy said: "Yes you can add more memory up to 16gb." Before I bought it I thought I read that I could upgrade the memory.