On Monday I let Google know about the problem and I was told that 100,000 impressions after a change to ad text or keywords your whole account is put on hold pending review. This doesn't include changes to campaign budgets or max CPC.
So, if you make/edit and ad and/or change keywords in an ad your whole account stops serving 100,000 impressions later.
I have a feeling that Google UK may be wrong about the whole account pausing, as the freeze seemed to be limited to the campaign I made changes in, with other campaigns serving normally.
My policy from this is not to change ad copy or keywords Fri-Sun so that ads will serve through the weekend.
Are there any more tips like this that should be a part of the Google Adwords FAQ?
Col
If you make a change to an Ad Group (ad copy or keywords) then that Ad Group will stop serving after 100,000 impressions on the account until the changed Ad Group has been reviewed by Google.
The reason my whole campaign had frozen was that I was sorting key phrases into better targeted ad groups, and so I made a changes to all of my ad groups in a single batch. 100,000 impressions later, they all froze awaiting review.
Col