I thought that the colour on the clock had changed last night when I updated, but the issue with picon transparency happened several months ago. Are you saying your picons were ok (as in transparent) up to the latest update? I ended up re-saving all picons using an image editor in order to resolve the transparency issue. I'll have to have a look through other posts to recall what I did at the time, but my picons are still fine - just the background or clock time has altered colour slightly.