Louise's mind's perception of time is altered and she can see into her own past/future, but she is not immortal (as per this Q&A) and can't see beyond her own death.
The Heptapods state that 3000 years into the future they will need humanity's help.
Keeping the above statements in mind, does it mean that at least one Heptapod lives to be more than 3000 years old and has 'seen' the need for humanity's help?
Do Heptapods have a life expectancy of more than 3000 years?
If not, then how do the Heptapods know that they will need help? Please explain.