Well, you can't really assign ownership in that fashion. First off, the "any later version" provision only applies to licenses published by the FSF:
Each version is given a distinguishing version number. If the Program specifies a version number of this License which applies to it and "any later version", you have the option of following the terms and conditions either of that version or of any later version published by the Free Software Foundation.
Secondly, you can't revoke rights previously granted. A project licensed under GPLv2 will continue to be distributable under the GPLv2 regardless of future license versions. So even if the GPLv4 says 'You have to sign your copyright over to the FSF, mwahahah' then you are free to ignore that change.
Each version is given a distinguishing version number. If the Program specifies a version number of this License which applies to it and "any later version", you have the option of following the terms and conditions either of that version or of any later version published by the Free Software Foundation.
Secondly, you can't revoke rights previously granted. A project licensed under GPLv2 will continue to be distributable under the GPLv2 regardless of future license versions. So even if the GPLv4 says 'You have to sign your copyright over to the FSF, mwahahah' then you are free to ignore that change.