Comment by mercora

The recursive resolver you describe would adhere to the same TTL as would do any reasonable public resolver. The difference in cache behaviour, if any, only depends on if the resolver already has a cached record that's still valid or doesn't have it. That it won't have it just happens to be more likely as the amount of requests your resolver received is smaller as the case if you are it's sole user. It's possible to force the behaviour you described by using specialised tools that are meant to be used for analysis like binds dig utility with its trace flag. It can bypass any resolver by querying up from the root servers to the designated label without any caches being involved. You still only will know that other resolvers will receive the desired answer eventually. Only safe bet is to assume it will take the TTL until every will receive the updated record.