bird3 package upgrades - graceful restart?

[Christoph via Bird-users]

Hello,

since we moved from debian packages to your package repo 
(pkg.labs.nic.cz) we probably will see more regular updates.

Therefor we are curious whether a bird3 package update will
interrupt packet forwarding on a BIRD3 BGP router?
For example now with the current pending update

apt list --upgradable
bird3/trixie 3.2.0-cznic.1~trixie amd64 [upgradable from: 
3.1.5-cznic.1~trixie]

Should we manually run
"birdc graceful restart"
before running "apt upgrade"
or is this done automatically on package upgrades?

best regards,
Christoph

relevant config snippets:

/etc/bird/envvars:
BIRD_RUN_USER=bird
BIRD_RUN_GROUP=bird
BIRD_ARGS=-R

bird.conf snippets:

[...]
protocol kernel {
        ipv4 { export all; };
        graceful restart yes;
        persist yes;
        learn yes;
}
protocol kernel {
        ipv6 { export all; };
        graceful restart yes;
        persist yes;
        learn yes;
}

template bgp bgp_base4 {
        graceful restart on;
        [...]