[OSM-legal-talk] Licensing a combined OSM adapted and CC-BY derived work

[Andrew Harvey]

I consume OSM data, adapt it for my needs by adjusting OSM geometries
to match CC-BY licensed aerial imagery, and then publish the result
publicly.

To comply with the OSM data's ODBL license, my published results
contain a notice that it is "based on data (c) OpenStreetMap
Contributors under the Open Database License
http://www.openstreetmap.org/copyright".

To comply with the CC-BY license, I also add that "In part derived
from [name of work], CC BY 3.0 licensed, [link to work]".

Is this okay?

However "CC BY 2.0, 2.5, and 3.0 are clearly  incompatible, thanks to
the attribution requirements that can't be met."[1] and "It is ... not
clear if the CC 4.0 licenses are compatible ... with the ODbL"[2].

With this in mind my modified data is of no use to OSM since my
improvements can't be reincorporated with OSM?

Is this correct or is there a problem with my logic?

Many thanks.

[1] https://lists.openstreetmap.org/pipermail/legal-talk/2015-July/008161.html
[2] https://lists.openstreetmap.org/pipermail/legal-talk/2015-July/008157.html