In T293570#7434336, @Draco_flavus wrote:

I have investigated the problem further. It seems not to be linked directly to the ws-exporter tool. After a minor change on one of the transcluded pages the page in the main space could be seen with the change. The pdf-file however was still with the old version of the text. A minor (null-)edit on the page in the main space was sufficient to make the tool generate the new version (maybe the purge action would suffice). However it was confusing, why the updated e-book could not be generated.

This sounds like normal on-wiki caching that can be resolved with purging, as you say. I suppose we could automate purging the cache of the wiki pages when the nocache=1 parameter is passed in, but I'm not certain this is something WS Export should be responsible for, as nocache=1 is supposed to refer to caching within WS Export, explicitly. The on-wiki cache exists for a reason and it is probably best for the users to manually purge it as needed. For this reason we will close as invalid, but please re-open if we've misunderstood or you feel there's something more we can do. Thanks!