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I'm not sure why people expect their delivery date to change just because the shipping time has changed. If you order an iPad today, and the shipping time says 4 weeks, that's because at this time based on production time and number of units requested, it takes 4 weeks for them to get an iPad produced and shipped. Then two weeks from now if someone orders an iPad and they have a shipping time of 2 weeks, it just means in that they got closer to catching up. And at that time they can pump one out in two weeks... but they still are in the middle of making yours.

That said, the chances of receiving your ipad early in this case, increases quite a bit. Mine was due to ship April 21, but I just got notice that it shipped. 10 days early. That's a pretty good difference! I ordered March 24th, btw.
 
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