I upgraded to latest Jetpack, and since I did not think that anything would go wrong I did not immediately check the installation. However, a couple of days later, I realised my Wordpress blog was clearly not reading my Jetpack edit-page at all, since it just seemed to be reading the unrevised 2012-theme page, and on further inspection Ifound that Jetpack had totally "disappeared" from its folder completely. I was very relieved that simply reinstalling Jetpack enable the last-saved CSS edit-page (on which I have worked for weeks) to be retrieved, and I thought all was well.
However, on doing a few CSS edits this morning, it appears all is not well. The first few I did this morning were fine but now I suddenly find:
1. When I save edit-page I now get continuous server-error messages, as if revised Edit page has not been saved.
2. However, when I reload Edit CSS, the new edits are there.
3. However, my blog is not reading these most recently saved edits, but only the previous ones only (up to those made about 60 minutes ago). Looking in Chrome Developer Tools I can only see the previous edits, not the new ones.
4. Furthermore, when I look at CSS Revisions, (on right-hand side of Edit CSS page), none of the most recent versions of saved revisions are listed.
5. Going into 'Compare Revisions of “Custom CSS Stylesheet”', the only two revisions available to compare are two from four days ago, not the ones I have made today, (since re-installing Jetpack).
All this seems to point to something fundamentally wrong. Can someone from Jetpack please help, as I have done a lot of work using Edit CSS and am dependent on it. I can no longer do any urgently-needed revisions of my Blog.