There is no difference. You need to add copyright banners to your program (source code headers, output of --version, etc.). There, you specify which GPL versions apply. If you don’t specify a version number, it’s not only v2 or later, but any GPL version ever published by the FSF. See Sec. 9 of the GPLv2:
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. If the Program does not specify a version number of this License, you may choose any version ever published by the Free Software Foundation.
There is no difference. You need to add copyright banners to your program (source code headers, output of
--version, etc.). There, you specify which GPL versions apply. If you don’t specify a version number, it’s not only v2 or later, but any GPL version ever published by the FSF. See Sec. 9 of the GPLv2: