Key Takeaways
- A preorder or drop webhook should fire on allocation, not on every stock-tick in the warehouse.
- Waitlist “you’re next” is operational. “Tell a friend for early access” is promo with STOP.
- Free is 1 device, 300 SMS lifetime, and 300 contacts. Platform price is devices plus send volume; drop retries still spend airtime.
- Checkout OTP stays off the drop-notify SIM.
- Idempotency is allocation-id, not SKU — one SKU has thousands of ticks.
Summary
Scenario 241 is ecommerce webhooks for preorder drops and B2B wholesale allocation — not checkout HMAC, not COD, not dunning, not RMA. Inventory systems chatter. Buyers need one honest “you have 15 minutes” text. Service pricing is devices plus SMS send volume. You bring the phone and operator credit. Free is 1 device, 300 SMS lifetime, and 300 contacts.
Business allows 15 devices: drop notify, OTP, wholesale, promo, region spares. Uncapped platform volume is not unlimited carrier SMS. Confirm events in Developer Center.
allocate · 15-min hold · not stock-tick
SKU increment is not a radio event
Preorder drop is not inventory noise
Subscribe to allocation or waitlist-promotion events. Ignore bin moves and cycle counts. Signed webhooks only. If the hold expires, one “released” SMS — not a loop.
Transactional SMS, webhooks, OTP.
If 8,000 people are waitlisted and you text every stock-tick of +1, you will empty the SIM and the plan SMS meter before the first buyer checks out. Cap fan-out. Prefer a digest or a position-band update.
Drop webhook matrix
| Event | SMS? | Failure |
|---|---|---|
| Waitlist joined | Optional one confirm | Unsigned join; bot list |
| Allocated / your turn | Yes — hold window | SKU-tick storm |
| Hold expired | One release notice | Retry loop shames the buyer |
| Wholesale PO approved | Buyer + warehouse, different templates | Retail drop copy on a PO |
Waitlist position vs “you’re in”
Position-band (“top 100”) at most once per band. “You’re in” is the only high-priority consumer. Referral promo is a different device with STOP. Google Ads SMS/MMS policy.
Wholesale PO webhooks
Retail drop language does not belong on a purchase order. Warehouse SMS is ops. Checkout OTP isolated. Live fields in Developer Center. DLR.
Devices, volume, and airtime
Drop night is a planned volume event. Budget platform sends and operator credit. Free (1/300/300) will not survive a hyped SKU.
Drop-night operations
Pairing, charge, OTP isolated, staff canary on a fake allocation. Setup, Downloads, pricing.
Decision guide
Ship when allocation-id keys exist and stock-ticks are silent. Delay if marketing owns inventory webhooks. No-phone-ops: aggregator.
Drop checklist
- Allowlist allocation / expire / PO — not bin ticks.
- Fan-out cap or digest.
- OTP isolated.
- Wholesale templates separate.
- Referral promo has STOP.
- Developer Center fields confirmed.
Next steps
Scenario 1 checkout, scenario 61 COD, scenario 121 dunning, scenario 181 RMA.
Related product pages
Jump to the live product docs for this topic—not another long-form article.
- SMS webhook integrationInbound and status events
- transactional SMS for orders and alertsEvent-driven messages
- SMS API documentationLive endpoint reference
- device and SMS volume pricingPlans and allowances
