The BC Boating Forum is reporting major errors -- ebbs shown as floods -- in current predictions for numerous passes. Hopefully the error is so big that many users will notice it (and Garmin will fix it quickly), because these passes have the strongest currents in all of North America:
http://www.cruising.bc.ca/boating_forum/index.php?topic=143.0
I suspect Garmin are using outdated Tide & Current almanacs because Navionics had this problem in BC waters 6-7 years ago and the problem was fixed using more up-to-date sources.