My Cap One secured card graduated a couple of months ago to a Cap One Platinum. Once it graduated I asked online chat if I could PC to a Quicksilver, to which I received a generic "not available at this time, thank you for being a valued customer" response. Since then I've been waiting for the "upgrade" option to become available under the 'offers' tab online. It still hasn't. I contacted customer service again through online chat and received the good news that they would PC my platinum card to a Quicksilver!
The SL is still a measly $500, so I did try to request a CLI as well but received a 2 - 3 day message. I tried reconning with the same chat agent who kept saying "please give me a moment" in 2 minute intervals. After 15 minutes, the chat agent came back and asked if I wanted to request a CLI on the website or through phone. By that time I just called a human csr who said there was no way to expedite a CLI over the phone.
Getting a QS is a small victory nonetheless!