With effect from 15 Apr 2018, your Lifemiles will only be extended for 12 months, following any earning of miles. Currently, your Lifemiles can be extended for 24 months following any activity on your account, which includes the earning and redemption of miles.
To recap, Lifemiles is Avianca’s frequent flyer programme, and depending on the sale, you can potentially purchase up to half a million miles for as low as 1.3-1.4 cents each.
Miles accrued before 15 Apr 2018 will continue to have 24 months of validity, while miles accrued from 15 Apr 2018 onwards will only have 12 months of validity. As per the website:
What this means is that if you are intending to purchase and/or redeem miles, you will have to work within a 12-month time frame to avoid getting yourself in a situation where your miles expire before you get to use them. This also implies that you should not hoard Lifemiles unnecessarily.
Full terms and conditions can be found here.