Please, there's no need for "serial posting." Instead of three posts in a row within minutes of each other, next time just edit the last post you made and add what you want to add.
I know there are a lot of projects out there these days - it's rare there's fewer than two dozen if not much more. Overall on Kickstarter, about 40% of their projects succeed, the bulk of which have goals of less than $20,000. (I attended a seminar at Kickstarter's headquarters last week, and there's three more I'm going to by the end of the month - going to be a busy one for me.)
But you still don't seem to understand the point I'm making. Even if the cards shipped to you immediately the very second your project ended, they might not even make it to you in under 30 days - not unless you had them shipped by a high-speed service like those offered by Federal Express, DHL or UPS. And that's certainly not going to happen, because it will take about two weeks just for you to receive your funds from Kickstarter, after they take out their percentage - 5% for themselves and between 3% and 5% for Stripe, their payment-processing company. So by about day 14 of your 30-day promise, you'll be able to pay for your decks to be printed - it's unlikely the printer will begin work before they're paid, so that would leave you a mere 16 days for them to receive your payment, clear their calendar of projects to get to yours, print it, ship it to you, then for you to repackage it and ship it to your backers. There is no way you're going to meet such a deadline.
Even if they are doing the fulfillment for you, where, exactly, is their fulfillment center? If it's in China, next to the printing factory, fantastic - they can ship straight from China to your backers and the deliveries might only be a couple of weeks later than you planned. But if the fulfillment center is anywhere else, especially if it's in the US, now you're back to having to wait for the cards to get from the factory to the center and your backers won't see their decks for at least a month PAST your 30-day deadline, if not more.
I'm not saying "Don't do it." I am saying "Don't promise what you simply can NOT deliver, not without bankrupting the project using overnight shipping or air freight."