One should definitely have outgrown a junior title after say 3 years of relevant experience, as that is more than sufficient time to be trained into a normal (non-senior) status.
It could last longer if your company does not have a normal title (i.e., they consider junior == !senior), but someone with 10 years of relevant experience should have earned a seniority title of some sort.
It could last longer if your company does not have a normal title (i.e., they consider junior == !senior), but someone with 10 years of relevant experience should have earned a seniority title of some sort.