Restarting the portal : ipfw rules are removed, but portal logic (dashboard) still shows logged in users

[Gertjan]

Version :

2.4.3-RELEASE-p1 (amd64)
built on Thu May 10 15:02:52 CDT 2018
FreeBSD 11.1-RELEASE-p10

Wen I change an option on the settings page of the Captive portal, all logged in captive portal clients are removed :

[2.4.3-RELEASE][admin@pfsense.brit-hotel-fumel.net]/root: ipfw table all list
--- table(cp_ifaces), set(0) ---
sis0 2100 1554 91029 1527754363
--- table(cpzone1_auth_up), set(0) ---
--- table(cpzone1_host_ips), set(0) ---
192.168.2.1/32 0 1324 65870 1527754363
--- table(cpzone1_pipe_mac), set(0) ---
....
--- table(cpzone1_auth_down), set(0) ---
--- table(cpzone1_allowed_up), set(0) ---
....
--- table(cpzone1_allowed_down), set(0) ---

But, according the Dashboard, the users are still logged in :

I'm using the FreeRadius package. When I switch to the Local user manager, the behavior is the same.

This is not a show-stopper, because I'm not changing options often (pretty close to never).