FreeBSD: git --count result differs from the number in output from uname -v

root@mowa219-gjp4-8570p:~ # date
Sat Mar 13 07:22:28 GMT 2021
root@mowa219-gjp4-8570p:~ # bectl list -c creation
BE                                                  Active Mountpoint Space Created
r357746-Waterfox                                    -      -          59.2G 2020-03-10 18:24
c2733-g5ac839029d-d                                 -      -          1.33M 2021-02-27 01:52
c2733-g5ac839029d-e                                 -      -          74.5M 2021-03-01 05:55
c2733-g5ac839029d-f                                 -      -          453M  2021-03-04 09:17
c257171-g0d3b3beeb253e09b2b6b3805065594aecc7e2c2f-a -      -          104M  2021-03-05 07:37
c257171-g0d3b3beeb25-b                              -      -          129M  2021-03-05 08:56
c257171-g0d3b3beeb25-c                              -      -          156M  2021-03-06 17:32
PkgBase                                             -      -          2.93G 2021-03-07 16:50
c257171-0d3b3beeb25-d                               -      -          134M  2021-03-10 22:41
c257171-0d3b3beeb25-e                               -      -          26.0M 2021-03-12 19:46
n257337-5fe0cd6503d34d23c98e9e1ff7bf10340218a5ec-a  NR     /          119G  2021-03-13 03:06
root@mowa219-gjp4-8570p:~ # git -C /usr/src rev-list --count HEAD
257337
root@mowa219-gjp4-8570p:~ # uname -v
FreeBSD 14.0-CURRENT #89 main-n245443-5fe0cd6503d: Sat Mar 13 01:13:00 GMT 2021     root@mowa219-gjp4-8570p:/usr/obj/usr/src/amd64.amd64/sys/GENERIC-NODEBUG
root@mowa219-gjp4-8570p:~ # uname -b
73f2153f6c841b57e31ce294d17592917ffb6ede
root@mowa219-gjp4-8570p:~ #