A GWX dev team member would probably have to answer that for you.
I think the timeline you get is from stock, but there were some errors as to which upgrades were available and when they were generally avaialble to front line commanders SO GWX changed the availability dates but there was no way to modify the time line?
at least i think that is what i read somewhere.
If im correct - the time line is more or less useless.
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