i think Kitty is a member of the team in 2013. I do not think she was a member of the team in 1963. i think she joined in 1980, and if you asked when she joined the X-Men, the answer would always be 1980 (or whatever the sliding-timescale of the Marvel Universe makes 1980) and never 1963 just because she later taught students who came from 1963 in 2013.
How big of an idiot can you be to say Kitty is one of the 05 just because she’s in charge of the time-displaced 05 in the present? It’s just the stupidest argumente ever and I can’t believe some people actually believe this. The only way for a mutant that was created AFTER X-Men v1 #1 (1963) to be considered an “original” X-Man would have to include a retcon that clearly states the mutant was trained by Xavier at the same time as the other 5. Like say this way

Kitty never time-traveled to the founding moments of the X-Men. Kitty was what, 5 years old when the X-Men were created? (considering she was 13 when she joined)

that’s her. Joining the X-Men. Uncanny X-Men #129-131, not Uncanny X-Men #1. Learn how to understand what you’re reading rather than just assuming shit.
I honestly can’t believe X-Fandom has dropped to such levels of stupidity. Idiots.
oh, but it has… Have you been to CBR’s forums lately?