Upgraded to 13.1 pkg doesn't see it

HI,

I upgraded to FreeBSD 13.1 from 12.3, but the package manager says I'm 
on 12.2. And it seems that the /usr/include/sys headers are from 12.3, 
so ports won't make. Where does pkg get the OS version?


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root@liberty [/usr/src] # pkg bootstrap -f
The package management tool is not yet installed on your system.
Do you want to fetch and install it now? [y/N]: y
Bootstrapping pkg from 
pkg+http://pkg.FreeBSD.org/FreeBSD:12:amd64/quarterly, please wait...
Verifying signature with trusted certificate 
pkg.freebsd.org.2013102301... done
Installing pkg-1.18.4...
Newer FreeBSD version for package pkg:
To ignore this error set IGNORE_OSVERSION=yes
- package: 1203000
- running kernel: 1202000
Ignore the mismatch and continue? [y/N]:

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Thanks,

Don