Photos will usually appear within 5 minutes of them being added to the album. Our team of moderators review the photos to make sure they are appropriate before they can appear on the live slideshow.
This time can vary depending on how many photos there are in the album already and when they were added. If there are a lot of photos in the album and it is added at the beginning of the slideshow, it might take a few minutes to go through some of the photos that were previously approved first. Also, if there are many photos added at the same time, it might take longer.