I have a significant amount of miles scheduled to expire at the end of July. I had a rental car that should have credited miles to my account, thus resetting the expiration date but the website says it could take 6-8 weeks for the miles to deposit and I'm not willing to gamble all my miles on that.

I was reading that the miles balance needs to increase to extend the expiration date. If a family member transferred miles to me, would that trigger the extension? I know I can purchase miles as a last resort but I'm looking for any other proven ways that have worked within the last 6 months for anyone.

Thanks so much in advance!