Coalition Tech "Client ABC" BigCommerce migration: 28,000 → 13,400 ranking keywords in 10 months

Claim: Coalition Technologies case study: client ("Client ABC") moved from old agency platform to BigCommerce. Ranking keywords fell from 28,000 to 13,400 within 10 months — a 52% loss — due to skipped redirects, content pruning, and lack of technical access during migration.

Source: Coalition Technologies case study (vendor-published 2024-2025).

Confidence: Industry-consensus (vendor case study; pattern consistent with UK retailer lost ~£3.8M in first month after botched migration — IT consultants rejected redirect mapping and [[sej-892-migrations-523-day-recovery]]).

Pairs with [[sej-892-migrations-523-day-recovery]] — the SEJ study reports the average shape; this case study shows the loss size when migration discipline isn't followed.