The limits to the number of photos per album DAKboard has access to currently:
Google Photos: 5,000
Apple Photos: 500
Microsoft OneDrive: 200*
Instagram: 10 most recent for a user, 25 for a hashtag
Reddit: 25 most recent
Out of that list, DAKboard can pull more photos from Onedrive than the current 200 respectively. We have enhancement request open for this currently.
For the other photo sources we are limited by the APIs we connect to. When the photo changes on your DAKboard, we grab a new photo out of the album by random between 1 and X, where X is the number of photos in the album (that DAKboard has visibility of).