Strange rejects the idea of training Illyana at the end of UX 191. It would make sense that he acted this way because he had been training the future Illyana and did not want to change history. He's also refusing disciples in DS2 57 and 58, which again makes sense if he has a time-traveling Illyana as a disciple by this time.Leoparis wrote: In this issue we have a Dr Strange from the past. He doesn't know Illyana Rasputin. He knows Peter Rasputin, and knows the X-Men well. He met the new X-Men in X-Men Annual 4 (1980).
He's apparently free to teach though it is not necessary that we look at a time when he didn't already have a student.
He discovered Illyana's existence in UX 190-191, the Kulan Gath Saga (Feb-Mar 1985).
Clea is Strange's disciple until Dr Strange 55 (Oct 1982) so that leaves several years where to place his appearance.
There is a gap between the time when Clea leaves Strange and the time when Illyana reappears from Limbo as a teen with her powers in X 160.
Spoiler:
Thzere is another related time travel in UX2 15.
My advice is to have UX3 7 after DS2 56 rather than before DS2 57 and I think it works best to extend the apprenticeship of Illyana. In UX3 15 the other students ask her "Where do you go when you're not here?" implying that she has made several back and forth time trips to apprentice under Strange since UX2 7, rather than have UX2 15 directly following from UX2 7 for Strange and Wong.
There are 8 issues between UX2 7 & 15 and ten Strange adventures between DS2 56 & 57 (DEF 106-109, M/GN 1 (37 - 62), DEF 110-117, M/S-HCOC 1-3, IH2 277-279, M/TIO 91, M/TU@ 5, M/TU 125/2, ROM 41-42, CRYS 3) so it's possible for Strange to have met Illyana a few times.
DOCTOR STRANGE/DR. STEPHEN VINCENT STRANGE
DS2 56
UX3 7
DEF 106
...
CRYS 3
UX3 15
DS2 57
MAGIK/ILLYANA RASPUTINA
UX3 6
UX3 7
UX3 8
WONG II
DS2 56
UX3 7
DEF 106
...
CRYS 3
UX3 15
DS2 57