Time change interferes with legendary islands in ORAS?

Question

I changed the time yesterday back one hour because I forgot to for the daylight savings. Now, when I go to the pathless plain in OR, Cobalion doesnt show up. Can I never get him again?

Answer 1

When you change your 3DS' clock, it's generally the case that you need to wait 24 hours before in-game events that happen depending on time to reoccur (e.g. the islands that appear daily).

Also, make sure you have 3 fully EV'd Pokemon in your party (doesn't matter what EVs, their 510 EVs just need to be all used). Cobalion also only appears under that circumstance.

Source: experience.