ICloud Photos: Disable and Delete on Ipad
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"Disable &amp; Delete" deletes only the photos and videos on iCloud. However, you would lose the originals of your photos and videos if "Optimize iPad Storage" were selected instead of "Download and Keep Originals" in your iPad's “Settings > [Your Name] > iCloud > Photos” settings prior to your selecting "Disable &amp; Delete". 

In addition, if your iPad has had little free storage left recently and "Optimize iPad Storage" were selected instead of "Download and Keep Originals", then you might also have lost some of the photos and videos you have been accessing the least in addition to originals of all your photos and videos. The number of photos and videos you might have lost in such a scenario (in addition to all of the originals of all photos and videos) would depend on how little free storage your iPad has had (if that were the case) recently.  

In summary, if “Download and Keep Originals” were selected in your iPad's “Settings > [Your Name] > iCloud > Photos” settings prior to your selecting “Disable &amp; Delete” (and you have had no trouble with the storage space on your iPad recently), you should not have lost anything at all. However, if “Optimize iPad Storage” were selected prior to “Disable &amp; Delete”, it depends. This relatively recent article explains “What Hap­pens When You Dis­able and Delete Pho­tos from iCloud” in more detail.