This may be a silly question but...........
I've had the same for my 800D that I bought last summer. It is running an older version of the firmware but everything works perfectly (or put it another way it gets used for wildlife and I've never found a problem with it). So given that my other camera, the 550D, is 8 years old, has never been updated and has also never had any problems, should I bother? And if I did, how do you do it? I guess copy the download onto an SD card but if the only ones I have are for images and I don't want to mess them up..........? Can you cable connect it to the pc like I do the satnav?