Is blepharoplasty permanent? Will the results of my blepharoplasty last as I age, or will my eyes continue to sag and possibly need to be redone? .

Blepharoplasty. No anti aging procedure last forever. You will continue to age. However, many people will only have one blepharoplasty and the results may persist for 15 years.
Blepharoplasty. blepharoplaaty is permanent and results should be long lasting. However you will continue to age and may need touch up surgery at some point. Have your eyes evaluated by a board certified surgeon with expertise in eyelid surgery.
No, but... Although no facial rejuvenation procedure result is “permanent”, the results of blepharoplasty surgery usually last for decades. Redoing upper or lower blepharoplasty surgery is infrequently necessary; if considered, much care must be taken to avoid overdoing the procedure ( and causing a complication).
Most . Most patients only have one blepharoplasty in their lifetime, but yes the results will change as you age. Our skin continues to lose elasticity, so will continue to change over time. Some patients do seek out a second blepharoplasty if they continue to have significant drooping, but this is fairly rare.
No. Repeated removal of skin around the eyes is not advisable. This can result in a shortened eyelid that will not completely close causing a chronic dry eye condition. Check first with your surgeon to determine if a browlift might be advisable, thereby limiting your need for removal of too much skin.