Nikon D6 Reference Manual page 559

❚❚ The Transfer Icon
Upload status is indicated by the transfer
icon.
u (white): Send (priority upload)
The picture has been manually selected
for upload. Pictures marked with this
icon will be uploaded before pictures
marked W ("send").
W (white): Send
The picture has been selected for automatic upload but upload
has not yet begun.
X (green): Sending
Upload in progress.
Y (blue): Sent
Upload complete.
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