The two-Gateway harness checklist in CONFIGURATION.md said a crashed
leader hands its providers over within lease_seconds + grace_seconds; a
peer only tries to acquire on its fixed lease_seconds // 3 tick, so the
worst case is one renewal interval more (50 s with the defaults), as the
leader-lease section of the same file already says. The grace_seconds
field description had the same shorter bound.
The channels.leader_lease comment in config.example.yaml still said web
UI credential changes reach the holder only when it next starts the
channel; since #6988 the holder applies them within one renewal interval.
The harness `check` footer still listed the IM channel gates as waiting
for leader election, which landed in #6843; it now points at the manual
channel item in CONFIGURATION.md, which also gains the runtime-config step.