So I was walking in Rock Tunnel 1, I applied a repel and I walked momentarily outside to Route 10 and back in, the repel outlay was still there counting my steps but the repel effect had stopped like 70 steps too early and I encountered wild pokemons.

 

I'm not sure if it's intentional to stop working after you leave a cave or something. I'd find that odd to be the case but even if it is, the repel counter overlay should be removed when the effect wears off in that scenario.

If the first pokemon in your party (fainted or healthy) have the same level or is below the level of the pokemon you encounter, the repel won't work.

Repel only works if your first pokemon is at a higher level than the wild pokemons.

Well damn. I can't recall which pokemon I had put first but I reckon that might be the case here. Good to know. Thanks.

 

Suppose this can then be closed.