According to the EarlyReturns Membership Guide, only accruals and not redemptions are considered activity for purposes of Mileage Expiration. Can anyone confirm that is in fact the case?

If so, what is the easiest and most reliable method of accruing miles prior to 06/30/14? Would transferring 1,000 Miles for $10 from another EarlyReturns account through Points.com do the trick?

If not, how efficient in your experience is ThanksAgain in posting miles to EarlyReturns? From my understanding, if I register and buy a cup of coffee from Carl's Jr at LAX, I'll accrue ~2 miles in EarlyReturns within 6-8 weeks?

And yes, that means without actually flying Frontier or signing up for their affinity card prior to 06/30/14.

No I can not, but reading the TOS, it sounds pretty cut-and-dried (bolding mine):

"Mileage in a Member's account will not expire so long as the member generates accrual activity in the account."

Looks like you need to accrue points at least every 18 months to keep 'em alive.

I'm up for renewal of my Frontier credit card and am thinking about canceling before the AF hits. I'm assuming that I'll have 18 months to use 'em or lose 'em (or perhaps apply for their credit card again in 14-16 months if I need to extend their life).

In case you haven't seen it, This article has some ideas.

I have, but the article is over a year old and I was hoping for some personal experiences from FT, especially when it comes to transferring miles through Points.com and ThanksAgain. While the article does mention transferring miles, it also mentions FTD, 1-800Flowers, and the EarlyReturns Shopping Mall, unfortunately none of which still are partners with F9.

I guess my question is not "How to extend my Mileage Expiration Date?" but "Should I use Points.com or ThanksAgain to extend my Mileage Expiration Date, or neither and why?"

And congratulations to myself on my 100th post

Indeed, and it comes from a notoriously lazy blogger whose only motivation is self-enrichment. Not a source I would rely on.

I note that the language in their agreement is pretty specific: it says "accrual activity."

I could easily see them interpret that to mean that transferring points in (eg from AMEX) might not qualify as "accrual" (technically you accrued points elsewhere and merely moved them in) - but call me cynical.

Anyway, I have enough points for a trip to someplace sunny on Frontier but do not have plans to use them for a year or so. I'm going to kill my Frontier mastercard tomorrow and take my chances. I figure that if I need to extend their life I can try a test transfer of the minimum Amex MR points in about a year; if that doesn't reset the expiration date I can always apply for another Frontier MC then, which should do the trick. Only risks are if they change the rules (always possible) or if they don't want to give me a credit card (which I'm going to doubt, since I'm in the process of divesting all my Barclay cards - I think I'll look good to them in about a year).

I'm guessing you didn't have any spend on the MC recently, or else the miles would be safe for 18 mo after then, more than enough for your year of break.

No, I've got my Frontier MC statement right here, ready to pay. I'm definitely good for 18 months. Just not sure how long it'll be before I use the miles, and looking at contingencies. I'm fine for a while.

I just transferred Amex points to Frontier and it extended my expiration date.

On points.com, some airlines allow small transfers out. In early 2013, I successfully extended Early Returns expiration by transfer 20 Us Air miles -> 4 Frontier miles.