In the past, musicians would have a CD release party. They would not pick the date for the party until they had the CD in their hands. So many things could go wrong, and you need to do the same.
Don't pick your “launch” date until your podcast is available to the public. If you're worried this will ruin your “Splash” into the public. It won't.
In the same way, being in the phone book will not make you famous – being in Apple podcasts will not make you a celebrity.
Don't Launch Without a Podcast
If your show isn't available on at least the top three options – don't launch. The name of the game is subscribers. Don't announce your launch date until you are in Apple, Google, and Spotify.
Apple Doesn't Happen Overnight
It can take 3-7 days with the worst-case scenario being two weeks (typically around the winter holidays). Keep in mind these are business days so don't submit your show on Friday and expect to see it on Monday.
Also, just being in the directory doesn't mean you will be a search result. As I write this Google Podcasts is in the Ios store (it was announced yesterday) but if you search for the exact name “Google Podcasts” it doesn't show up. So you want a little more time for your name to propagate through the system.
Don't Make Them Search
I've made videos about how bad search is in Apple, and with this in mind make sure the direct link to your show in the different platforms is available on your website so people don't have to “find you” in these directories.
Need Help With Your Launch?
If you need help launching your show, please contact me and let's set up a time so I can help you maximize your podcast launch.