I now believe that it is specifically the contour placement method that's the culprit. It labels fine dynamically but when exporting to static annotations it drops (in my case) 73% (a VAST majority) of the labels. Also, the problem seems to get worse with the number of contours; the more contours I need to label the less exported static annotations I get. When the dataset contains up to 15000 contours and the Countour method is selected, the export will still drop labels but not as many. When labelling 50000 contours only a fraction of the labels convert and so on... Workaround: Changing the method from Contour placement to Regular placement method retains ALL the labels in the same positions but you loose the nice laddering options.
In case anyone wonders why i need to label so many contours; we're building a high quality topographic basemap for a web GIS system across a vast geographical area and at 14 different scale levels down to 1:1500. At each scale level the interval of the contours changes and each scale level is more and more details as we zoom down. I need static annotations because we are masking the lines bellow the labels. Once finish we export these projects into a tile package to be used as basemap services on the server.
