This is a Mileaholic exclusive.

I have confirmed that this tactic works as I have done it myself.

Here is what you do. Open an Amex Platinum Business card in December.  Ideally you want to open it the end of the first week of December. You want enough time to purchase $200 in (preferred) airline gift cards (2 x $100 to be safe) and enough time for the system to credit you in the year of that December. Credit should post with in a week or 2 (at most)

Preferred Airline as in the one you chose as soon as your account shows online. I can verify that Southwest and American gift cards will work. Purchase them directly from AA.com or Southwest.com.

Now, once the next year rolls on in January, you may repeat the process and purchase another $200 (2x $100) in gift cards. The cool thing here is that you can actually change your preferred airline anytime, once in January. Note: This change is the one and only time you can do this until the next January. So if you opened the card and chose Southwest as your preferred and collected $200 in Southwest gift cards, you can do Southwest again in January and collect another $200 then switch it to AA after you get credited. Or switch to American as your preferred once January comes then purchase $200 in AA gift cards. 

So far you should have $400 in gift cards. You should have already paid the $450 in annual fee back in your first billing cycle. We currently stand at -$50. We aren't done yet. Let the gravy train continue...

Fast forward 12 months later...

Now the next January rolls in. This month your annual fee is due again. But January 1st you should go ahead and purchase $200 in gift cards in whatever airline you wish, just make sure you change the preferred airline first. Wait for the credit to post and then cancel the card when the annual fee appears. Make sure the rep puts in a request for credit of the annual fee since you will be closing the card within 30 days of the annual fee posing.

Example:

This example will show you how to get $600 Southwest Gift Cards. Of course you can mix and match with American however you please.

Early December 2017

• Open Amex Platinum Business card
• Pay $450 annual fee.
• Select Southwest as Preferred Airline.
• Buy 2 - $100 Southwest gift cards at Southwest.com.
• Get reimbursed $200 a week later.

Early January 2018

• Buy 2 - $100 Southwest gift cards at Southwest.com.
• Get reimbursed $200 a week later.
• Change preferred airline to American Airlines.
• Chill for rest of the year

Early January 2019

• Stop chill
• Change preferred airline to Southwest Airlines.
• Buy 2 - $100 Southwest gift cards at Southwest.com.
• Get reimbursed $200 a week later
• Call or secure message Amex and cancel card and request annual fee credit      (No later than 30 days of annual fee posting)

Congratulations you scored $600 in airline gift cards for only $450!

Pat your self on the back...you enemy of credit card companies, you.

Another reason that Amex Platinum business card is one of the most valuable out there. This should incentivize you to open the card every December regardless if you are eligible for a bonus or not.