While the collection is still unrevealed, since these fics are in medium (or bigger) fandoms, chances are those fics won't be on the front page of said fandom. As an option, if you'd like, go ahead and forward date your fic to July 10th or July 11th, whatever is the most forward time in your time zone (I wouldn't recommend going beyond July 11th or continuing to forward date more than once). This way your fic is on your fandom's front page when the collection opens. Otherwise, when the fics are revealed, it probably won't get any foot traffic from people checking out new fics in the fandom because it'll be a few if not more pages back.
To do this, you'll need to edit your fic and scroll down until you reach the Associations box. Towards the end of that box is a ticky box for "Set a different publication date." Ticky it to set the date to July 10th or July 11th or some other date. Then scroll all the way down to click on Post Without Preview.