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Using QGIS 2.18 “Las Palmas”
Created a map to print using the “New Print Composer” extension.
When working on this all polygons are perfectly in place.
Once the map is saved as a PDF/Image the polygons shift.
Extra info: Bing map (Base Map from Open Layers Plugin) and all polygons are set to ESPG:29902 TM65/Irish Grid