Change License to Creative Commons?

The Haskell report is currently licensed under a specific license which has its own entry in the SPDX database: https://spdx.org/licenses/HaskellReport.html
Unfortunately, the text in the SPDX database is worded in a way which implies that the license can only be used for the original Haskell 2010 language report, and no other version. The part of the license that cannot be modified reads:

> Code derived from the document "Report on the Programming Language
Haskell 2010", is distributed under the following license:

> The authors intend this Report to belong to the entire Haskell community, and so we grant permission to copy and distribute it for any purpose, provided that it is reproduced in its entirety, including this Notice. Modified versions of this Report may also be copied and distributed for any purpose, provided that the modified version is clearly presented as such, and that it does not claim to be a definition of the Haskell 2010 Language.

Maybe if @simonmar, as the current holder of the copyright, gives his heads up we can change the license to a creative commons license. I think CC-BY-SA corresponds most closely to the original intent of the license. (The "provided that it is reproduced in its entirety, including this Notice." part of the license would correspond to the -SA part).

Review the current Haskell Report license text and the linked SPDX HaskellReport entry, then follow the discussion with the copyright holder about whether CC-BY-SA is appropriate. Done requires an agreed licensing decision and the report's license being updated consistently with that decision.

Written by the indexing model from the issue text.