About what?
To answer your question, Id have to see the transcripts. From what I have seen, there is an early statement, then a later one where he says something about reaffirming something about his earlier testimony. I have not seen the earlier transcript or the later one, so I do not know if the charge against him is valid or not.
I do believe it is unlikely to result in a conviction, because of the convoluted reaffirmation of a prior convoluted statement, but who knows what a jury will do, if it gets that far.
They have to prove intent to lie to congress, and with all the words in there, it gets very confusing, even to the reader, what Comey was affirming and not affirming. Not a case I would take if I were still a prosecutor.