Zone matching stays conservative
TaxiRates does not assign a street address to a Gander zone until the local boundaries are mapped. That prevents a plausible-looking but unsupported $8 or $12 result.
Airport direction matters
The schedule explicitly says from any zone to Airport. TaxiRates therefore returns $15 for Gander to YQX and holds the reverse trip for verification.
Why the Gander calculator sometimes stops
The Town schedule is simple once the zone is known, but an address cannot be assigned to an $8 or $12 zone merely because it looks close on a map. TaxiRates waits for mapped zone geometry before converting arbitrary streets into those published amounts.
The $15 airport rule is also directional in the source. The calculator applies it from a Gander zone to YQX and does not silently assume the reverse trip is identical.