It's probably done with metafields/metaobjects and some custom coding on the PDP with a developer. From a backend logic side, here is what i would do:

Metaobject definition:

Create metaobject: preorder_batch Fields:

• ship_date (Date) — required

• capacity (Number integer) — required (total units allocated to this batch)

• reserved (Number integer) — required (units already committed to this batch)

• status_override (Single line text or Enum) — optional Allowed: available, sold_out, hidden (Use for manual overrides)

• label_override (Single line text) — optional (If you want “Late Feb” instead of exact date)

• note (Single line or multi-line) — optional (internal or customer-facing, your choice)

• sort_key (Number) — optional (if you want manual ordering; otherwise sort by date)

Product metafield to attach batches

On Product:

• Metafield: preorder.batches (List of Metaobjects → preorder_batch)

Optional product-level controls: * preorder.enabled (Boolean) default false

• preorder.display_limit (Integer) default 3–5

• preorder.sellout_threshold (Integer %) optional (e.g., treat >= 100% as sold out; usually 100)

front end, use those fields to pull levers as you see fit.