Garmin releases 4 CNE and CNNAM versions a year.
Garmin purchases from Navteq maps and they become City Navigators versions we get-
Garmin goal is to be 4 months (Q) behind Navteq -
Usually updates are released in January, April, July and November-
.31 or .32 or .30a .30b versions are just errors corrections versions and are free updates for subscribers-
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