It depends. I think there are a mix of full and Juliet balconies throughout the resort, including on different floors. I know for sure that at club level on the 5th floor there are both full and smaller balconies and I think it is the same on other floors. All first floor rooms have a patio, I believe.
Your best bet to ask for a full balcony for a stay at the Beach Club is to request "Full balcony, please" on your reservation.
For a little more info, read this post from the Yacht & Beach Club FAQ thread:
Post 13: FAQ BC vs. YC, Room View Categories, Full vs. Juliet Balconies, Daybeds, Online vs. In-person checkin
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