Some are sure now, but may mistake and become unsure tomorrow.
There is so called International Socionics Institute in Kiev with founder Bukalov. That Bukalov thinks himself as ILE. Just look at this shy and quiet "ILE".
There was Lytov, who made a lot Socionics stuff and after many years accidently changed the opinion about own type ILE->LII.
There was Popov, who recently have changed opinion EIE->IEE.
Those were not just "dudes from the forum". They made researches, studed others, typed a lot, etc.
So when I get doubts in anyone's type there is sense to say them to check it.