Complex sentence: Trains serve every station on the route, except that peak services from Westferry to Canary Wharf do not call at West India Quay because they are routed along a different track to avoid junction conflicts.
Split into simpler sentences: Trains serve every station on the route with the exception of peak services from Westferry to Canary Wharf. These services are unable to call at West India Quay because they are routed along a different track to avoid junction conflicts.