Choices, choices, choices

Trying to choose my last coffee of the day. In the end I plumped for the Lungo.

I try and have my last coffee around 9pm. This was because I was under the impression that your body metabolised caffeine in around 3 hours. However after doing a quick search to confirm this "fact", I have discovered that it takes on average 5-7 hours. This means I need to take my last cup at 5pm, or play fast and loose, hoping I am at the quicker end of the metabolism scale and have it at 7pm. Not sure I like this new piece of knowledge.