I'm going to disagree with Krensky for 3 reasons.
1. I made the assumption that the ability granted 3 feats the first time I read it.
Shut up Jackson, that picture isn't even from the movie.
2. The feat is a carry over ability from the Tactician Expert Class in SC 2.0 which granted multiple feats.
3. The feats wording:
"At Level 6, you gain 1 temporary Basic Combat feat
at the start of each adventure until the adventure’s end.
At Levels 12 and 18, you may use this ability
1 additional time per adventure."
The level 12 and 18 legacy abilities allow you to use the ability multiple times but do not modify the time which the ability is used. You must still select the temporary feats at the start of the adventure. Be able to change the feat you select at the start of the adventure at the same time you select the original feat is useless.