In my experience, yes you can transfer whats left on the remaining 30 year lease to a new buyer. In your case thats what i would offer any buyer. If the land owner agrees to making a new 30 year lease , then the existing lease can be cancelled, there will be a fee at the land office to create a new 30 year lease, if the land owner will agree.
Forget about what people tell you that you can have a 30 + 30 + 30 lease , its absolute nonsense and also illegal , the maximum is 30 years only.