A quick Google search reveals:
The program has just announced an adjustment to their mileage expiration policy, which is worth being aware of. As if April 15, 2018, Avianca LifeMiles is modifying their mileage expiration policy:
Currently miles expire after 24 months of inactivity, and any sort of mileage activity (including earning or redeeming miles) extends the expiration date of your miles
Under the new policy, miles will expire after 12 months of activity, and only earning miles will extend the expiration date of your miles (meaning that redeeming miles will no longer reset the expiration date of your miles
Miles earned prior to April 15, 2018, will continue to have the old expiration policy, while miles earned as of that date will be subjected to the new rules.