"When you see her, tell her everything."

Translation: Až ji uvidíš, všechno jí řekni.

[ion1122]

The answer has first "ji" and then "jí". (That is, without and then with the diacritic mark.) Is that correct?

[endless_sleeper]

Yep. The first JI is accusative, the second JÍ is dative.

[Chris900231]

Can you use Kdy instead of Az?