The arrival of the first chromebooks

The Chromebooks finally arrived! I spent an afternoon setting up 18 of them and they were eagerly tested the next morning. Unfortunatly that was when I hit a HUGE snag. I won't bore you with details but in short after a few logged in things went bad. Others wouldnt login, and ones that were went horribly slow and then I started getting EEKS from around the school as the phone system was crashing.
Have you have ever had 18 annoyed primary kids wanting to know why their new toy isn't working while the office staff are pissy cause their phones are dead? Not a good afternoon. I did some digging and calling round. Sadly googles support was quite a mirror of microsoft. People barely able to speak english who just didnt understand what I was asking.
But anyway, I think I may have an answer. The chromebooks were shipped with version 14 and then were trying to automaticaly update all at once to version 20. I havent figured out how big this is but suspect its about 330mb in size. 18 laptops trying to download 330mb of data all at once on a single crappy adsl connection (which is shared by the phones) is not a good idea.
So what to do....... I downloaded chromes version of a rescue disk and did a restore on each laptop. Which upgraded the software to the latest version. This was done on a Saturday afternoon. Now to wait for Monday to see if it worked..........