It's really helpful to set up a teaser page as it can help you gather followers for your launch and ultimately on the launch day, they all will receive an email notifying them about your launch. This can help you collect more support on the launch day.
In my opinion, try to schedule your launch to the maximum amount allowed to do, that is 1 month so that you can promote your product as much as possible till your launch day.
Btw, I'm launching soon my first product! If you're interested, don't miss out on the AI business name generator I'll be launching (https://www.producthunt.com/prod...).
It can really be helpful to you for naming your product.