Picture your backyard in the middle of spring with a dedicated shucker cracking open cold ones while your guests stand around waiting for the next round. Mid-week shoulder months are the sweet spot for booking this kind of catering because caterers have open slots and you avoid weekend surcharges. If you want this setup to run smoothly, lead-time is your real lever for locking down the best price.
You need to book the shucker at least six weeks out so you can nail down the oyster varieties and delivery times without a rush. Once you lock that date, you can map out the rest of the party supplies and spread the total cost over time so it doesn't wreck your normal monthly spending.
Just remember that the 0% intro APR for 15 months on purchases and balance transfers is a hard deadline, not free money. If you still carry a balance when those 15 months run out, interest will kick in on what is left.