I tried all the above, in vain.
eexcept the suggestion about icloud. I can't figure out how to switch that off.
Another forum explains in detail how to renstal IOS 8.02 throgh iTunes with USB. It took me two hours to do all that. 3G was restored, I thought it was fixed. Next time I switched the ipad back on, "No Service" was back in the top left corner.
APple cannot afford to abandon the Ipad2 uiers so I'm sure this will be fixed in a next IOS update. In the meantime, this *****.
IT would be nice if Apple at least had the decency to make an official statement on this. I hope they are better at programming than at customer service.