Here is the thing. You may get a 10 year ban, you may not. I self deported 1.5 years ago. When I was leaving, all they did was look at my passport to see if it matches the name on my ticket, didnt look for a visa or anything(i obviously overstayed). I tried applying to come and visit my parents about 4 months ago, and I was denied, but on the fact that I havent dont have strong enough ties to the UK(i am polish) and nothing whatsoever was said about my overstaying. I also know someone else who overstayed and was let back in legally on a tourist visa soon after. Its basically a gamble whether you get the ban or not, because their system is so messed up.