Source upgrade 12.4 - 13.2 installworld jails Function not implemented

Hi all,

Looking for advice what to do next. This is a production server and we 
can only afford short downtimes.

Kernel is (was)
FreeBSD 12.4-STABLE stable/12-c3bbba00e GENERIC
then
Fetched 13.2-STABLE sources yesterday morning.

Did,
make buildworld
make kernel
make installworld

etcupdate applied in between

Did not reboot between kernel and world because wanted to save time, 
perhaps stupid.

Now that I want to upgrade the jails,
make installworld DESTDIR=$jail

It stumbles on the first cp from the temporary dir

mkdir -p /tmp/install.12dw9HKg
progs=$(for prog in [ awk cap_mkdb cat chflags chmod chown cmp cp  date 
echo egrep find grep id install   ln make mkdir mtree mv pwd_mkdb  rm 
sed services_mkdb sh sort strip sysctl test true uname wc tzsetup 
makewhatis ; do  if progpath=`env 
PATH=/usr/obj/usr/src/amd64.amd64/tmp/bin:/usr/obj/usr/src/amd64.amd64/tmp/usr/sbin:/usr/obj/usr/src/amd64.amd64/tmp/usr/bin:/usr/obj/usr/src/amd64.amd64/tmp/legacy/usr/sbin:/usr/obj/usr/src/amd64.amd64/tmp/legacy/usr/bin:/usr/obj/usr/src/amd64.amd64/tmp/legacy/bin:/usr/obj/usr/src/amd64.amd64/tmp/legacy/usr/libexec::/sbin:/bin:/usr/sbin:/usr/bin 
which $prog`; then  echo $progpath;  else  echo "Required tool $prog not 
found in PATH 
("/usr/obj/usr/src/amd64.amd64/tmp/bin:/usr/obj/usr/src/amd64.amd64/tmp/usr/sbin:/usr/obj/usr/src/amd64.amd64/tmp/usr/bin:/usr/obj/usr/src/amd64.amd64/tmp/legacy/usr/sbin:/usr/obj/usr/src/amd64.amd64/tmp/legacy/usr/bin:/usr/obj/usr/src/amd64.amd64/tmp/legacy/bin:/usr/obj/usr/src/amd64.amd64/tmp/legacy/usr/libexec::/sbin:/bin:/usr/sbin:/usr/bin")." 
 >&2;  exit 1;  fi;  done);  if [ -z "" ] ; then  libs=$(ldd -f "%o 
%p\n" -f "%o %p\n" $progs 2>/dev/null | sort -u | grep -Ev '\[.*]' | 
while read line; do  set -- $line;  if [ "$2 $3" != "not found" ]; then 
echo $2;  else  echo "Required library $1 not found." >&2;  exit 1;  fi; 
  done);  fi;  cp $libs $progs /tmp/install.12dw9HKg
cp: /usr/lib/libbz2.so.4: Function not implemented
cp: /lib/libc.so.7: Function not implemented
...
Goes on for every item.

So, any recommendation on what to do next? The host and jails still run 
as they should with the 12.4 kernel.

Reboot?
Fetch new 12.4 sources, build and reboot and start over?
Other suggestions?

Thank you in advance,
Per