“Catch You Later” Does Not Arrange a Later Meeting

In Australian speech, “Catch you later” is a common way to say goodbye. It does not mean that a meeting later in the day has been arranged; the whole expression is closer to “see you around”. It is not uniquely Australian: Cambridge also lists it as an informal farewell in general English.

A: I’m heading off. Catch you later.
B: See you.

It suits friends, colleagues finishing work, or people leaving a social gathering. If a real time must be arranged, say “I’ll see you at six”. In a formal setting, “Goodbye” or “See you tomorrow” is clearer.

https://www.abc.net.au/education/learn-english/learn-english-aussie-slang/7289548
https://dictionary.cambridge.org/dictionary/english/see-catch-you-later