The supply problem
Audemars Piguet is the smallest of the Holy Trinity by output: ~50,000 watches per year compared to Patek's ~62,000 and Vacheron's ~30,000. The Royal Oak represents roughly 80% of AP production; the Code 11.59 (2019 launch), Royal Oak Concept, and Millenary together cover the remaining 20%. Royal Oak production is therefore ~40,000 pieces per year across all variants, against demand estimated at 4-6x that volume.
The allocation game
AP distributes the limited supply through ~250 authorised dealers globally, plus AP-owned 'AP Houses' in major cities. Each dealer receives a small annual allocation (often <50 Royal Oaks per year for major dealers, <10 for smaller). Walk-in customers don't get Royal Oaks; the watches go to existing AP customers with documented purchase history. Building that history typically requires buying 3-5 less-allocated AP pieces (Code 11.59, Royal Oak women's references, Millenary) over 2-4 years before the AD will offer the Royal Oak you actually want.
What's hardest
Royal Oak 'Jumbo' 16202 (39mm thin, Genta-spec): hardest. Royal Oak Chronograph 26240ST: very hard. Royal Oak Selfwinding 15510ST (41mm): hard but possible after 2-3 year AD relationship. Royal Oak Offshore (chunky 42-44mm sports versions): more accessible. Royal Oak in gold or precious metals: most accessible (less waitlist pressure because gold prices already filter the buyer pool).
What you can actually do
Build the AD relationship: 2-5 year horizon, multiple smaller-allocated purchases. Buy grey market: 1.5-3x retail with no warranty. Buy pre-owned: similar pricing to grey market but with potentially better condition history and dealer warranty. Switch references: the Royal Oak Offshore line is more accessible than the original 'Jumbo' line; the Code 11.59 has stock available. Switch brands: the Vacheron Overseas (Genta-design integrated sport peer) and Patek Aquanaut are similarly hard; the Lange Odysseus and IWC Ingenieur SL Mark XX are more accessible alternatives in the same genre. See /styles/sport/.