Source package now created and uploaded successfully. If I try to upload it again I get this, which rather proves the point:
chris@desktop:~/debian/popout3d$ dput mentors ../popout3d_1.5.0_amd64.changes
Package has already been uploaded to mentors on mentors.debian.net
Nothing more to do for ../popout3d_1.5.0_amd64.changes
chris@desktop:~/debian/popout3d$
What have I done wrong now???
Chris