Wrong values in MapPokemon.ExpirationTimeMs

[Metalick]

Dear friends,
I'm getting wrong values for MapPokemon.ExpirationTimeMs. When I use WildPokemons.TimeTillHiddenMs it works perfect but I always get a different wrong value for MapPokemons.ExpirationTimeMs. Is that an issue or I shouldn't use MapPokemons.ExpirationTimeMs on that way?

Thanks in advance ;)