Great — here’s a focused guide to maternity/nursing bras that work for fuller busts (D through K cup) plus where to look in Australia and what to prioritise.

Quick summary

• Best types for D–K cups: full‑cup wired nursing bras (proper underwire shaped for a larger cup), high‑coverage wirefree/contour bras with A‑frame or dual‑cup options, and supportive sleep bras/bralettes for overnight use.
• Brands that cater to D–K (or large cup ranges) and are available to Australian shoppers: Curvy Kate, Playful Promises, Hotmilk (Preggi/Hotmilk), Bravissimo/Bravado lines, The Foundation / specialist fuller‑bust retailers. (en.wikipedia.org)

What to look for when shopping (essentials for D–K)

• Correct underwire shape: if you choose wired styles, the underwire must fully encircle breast tissue without sitting on it — many fuller‑bust brands use deeper, wider cups and longer underwires. (en.wikipedia.org)
• Wide supportive band with multi‑hook fastening (3–6 hooks) so the band remains the primary support as cup weight increases. (preggicentral.com)
• Wide, padded or molded shoulder straps and reinforced seams/bones at the side for lift and to prevent straps digging in. (theguardian.com)
• Nursing functionality that works for you: one‑hand drop clips, dual‑cup/overlap panels (helpful for volume fluctuation), or full‑panel easy access — try those that combine support with easy access. (preggicentral.com)
• Size range and conversion: many brands use UK sizing (common for larger cups); check AU↔UK cup conversions and consider sister sizes if band or cup fit is off. Specialist retailers list extended sizes (e.g., up to J/K in UK sizing). (thefoundation.com.au)

Recommended brands / places to shop (good for D–K)

• Curvy Kate — specialises in D to K cup ranges (lingerie and supportive styles). Good for structured underwire and full‑coverage shapes. (UK‑based but ships internationally/stocked by some AU retailers). (en.wikipedia.org)
• Playful Promises (Australia site) — carries DD+ fuller bust collections and a range of band/cup sizes; offers some styles suited to nursing or fuller bust comfort. Good for fashion + fuller sizing. (aus.playfulpromises.com)
• Hotmilk / Preggi (Hotmilk maternity lines) — widely recommended in AU for maternity/nursing bras with multi‑fit cups and extended cup options (wirefree and wired nursing bras designed for cup fluctuation). Look for their Serenity/Hotmilk lines. (preggicentral.com)
• Bravissimo / Bravado (and other fuller‑bust specialists) — known for supportive nursing bras and styles that work up to large cup sizes; good fitting expertise. (theguardian.com)
• Specialist Australian retailers (e.g., The Foundation Lingerie, Curvy boutiques) — they stock extended sizes (examples: GG–J and beyond) and can help with measurements and fittings. (thefoundation.com.au)

Style suggestions by need

• Everyday nursing bra (most support): full‑cup wired nursing bra from a fuller‑bust brand with wide band and strong straps (best for D+ where shape and back support matter). (en.wikipedia.org)
• Comfortable, fluctuating size: dual‑cup or multi‑fit wirefree nursing bras (these adapt to changes in cup volume during pregnancy and breastfeeding). Hotmilk/Preggi offer multi‑fit options. (preggicentral.com)
• Night / low‑pressure: soft, wide‑band sleep bra or stretchy bralette for leaks and comfort overnight — not for heavy daytime support. Specialist sleep bras in fuller sizes are available from maternity ranges. (preggicentral.com)
• Special outfits (strapless/multiway): look for fuller‑bust specific strapless/multiway bras (Curvy Kate, Curvy Kate Luxe, etc.) — many mainstream strapless bras fail on D+ so buy strapless that advertises D–K support. (womanandhome.com)

Practical buying & fitting tips

• Get professionally measured if possible (many Lingerie/Antenatal stores in Australia offer fittings and stock extended cups). Specialist shops are worth it for D–K ranges. (thefoundation.com.au)
• Try sister sizes if the cup or band isn’t right (e.g., if band feels tight try a larger band + smaller cup). Use the retailer’s AU↔UK conversion chart. (thefoundation.com.au)
• Expect to re‑fit: breast size commonly changes during pregnancy and again after birth; plan to buy 2–3 bras (one for pregnancy expansion, one for early breastfeeding, one for later). (preggicentral.com)
• Read return policies (maternity bras often need trying on) — choose sellers with easy returns/exchanges. (preggicentral.com)

Where to start right now (AU‑friendly links / retailers to check)

• Specialist fuller‑bust shops online in Australia (The Foundation Lingerie, Curvy boutiques). (thefoundation.com.au)
• Hotmilk / Preggi maternity lines (good local availability for maternity/nursing). (preggicentral.com)
• International fuller‑bust brands that often ship to AU or are stocked locally: Curvy Kate, Playful Promises, Bravissimo/Bravado. (en.wikipedia.org)

If you want, I can:

• Search current Australian stores for specific models in your exact band + cup (I’ll check stock & prices), or
• Show 4–6 specific nursing bra models for D–K that ship to Australia with price/size availability.

Which would you prefer?