A small point of clarification on this promotion, doubloons you already have on your account from previous purchases or events can be used for this promotion.
We have added this point to the portal article:
Say you have 20k doubloons on your account from saving / previous events, and decide to spend them in conjunction to an additional 5k purchased doubloons, you would be eligible for the T61.
If you've been in the market for some T10 perm camo, Tech Tree prem ships or free EXP converted this is a great opportunity to get a bonus!
Just make sure you hit the "Participate" button before you spend them!