Photo log: a photo that can't load now says so

Housekeeping on the photo log, found by going back over it looking for trouble rather than waiting for it.

• A photo whose file is missing now says so. If the underlying image is gone — deleted outside the app, or a record left pointing at nothing — the tile shows Preview unavailable. Previously it kept asking the server for a fresh link and retrying, over and over, for as long as the page stayed open.
• Report dates read in your timezone. On a report built late in the day, the date under a photo could briefly show tomorrow's date before correcting itself. It now shows your local date from the start — the same day the photo log files it under.
• Building a report from a big selection tells you the truth. A report holds fifty photos. Select more than that and it now says how many are being left out before it builds, instead of quietly trimming.
• Staged photos you never got around to uploading no longer hold onto memory after you navigate away.