I'm not understanding everything, so be patient with an old dog. Also, this is more of a problem with WMFLabs.
WMFLabs currently doesn't copy over a dump until everything is completely finished. For smaller dumps, the dump was finished and copied over to WMFLabs relatively quickly. For larger dumps (enwiki, dewiki, frwiki) it would take 1-3 weeks, thus became useless for my purposes. Therefore, for the larger languages, I'd manually copy the specific file in the dump I use.
Now with the new changes. In theory....
1) No language will be copied over for over a week after the dump has started.
2) The majority of languages (ie small ones) will be finished within the same short window.
3) For me, the majority of dumps are now rendered useless by the time they are copied over to WMFLabs.
I say "in theory" because I noticed some of the real small languages have finished within 4 days.
Bryan