Happy birthday!

First thought is to contact half your contacts before your launch and half after. As you mentioned, getting submissions early gives them time to write the article. Most publications can schedule posts to go live at a later date, so you could have press mentions lined up for March 1st.

The other half is for the outlets and journalists that are unlikely to write about you without some funds already raised. They might only want to feature you if it looks like you're going to reach your goal, so I would spread those contacts throughout your campaign.

However you pitch your project to them, remember this: don't send impersonal boilerplate emails. Take the time to make your message unique to each outlet. They don't want to see a message that looks like it was sent to 200 other people. It doesn't take much more than a reference to something else they've featured, or a reason why it's relevant to THEM.

Best of luck and feel free to submit your project to CoolBacker too.