Permanent retainer for 16 years to Vivera

Hi! I've had permanent retainers for 16 years, and they just came off today for Vivera ones (the metal was coming up and catching my taste buds). Originally, they told me to only wear the retainers at night, but then they said they weren't sure because of how long I've had the permanent retainers for, so they had me wear them when I left. In other peoples' experience, should I be wearing my retainers 24/7 even though I had the permanent ones on for so long, or can I only wear them at night? Thanks!