Is this Apple device still in your network: 2c:f0:ee:06:ab:96?
If it is not, then the reason code 8 is purely down to the fact that the STA has "Disassociated because sending station is leaving (or has left) BSS"
Here is an extract from Ruckus Support:
When disconnecting from an AP, what does reason code X mean?
SummaryThis article provides insight into the
reason codes for why an unsolicited notification management frame of
type Disassociation, Deauthentication, DELTS, DELBA, or DLS Teardown was
generated for a UE. This article lists the various reason codes along
with a basic description.
QuestionWhen disconnecting from an AP, what does reason code X mean?
Customer EnvironmentThe customer operates any WIFI access network, where the 802.11 standard is adhered to by access points and UEs.
Root CauseAn AP may disconnect a UE for any number
of reasons. These reasons are provided to the client by way of a reason
code supplied in an unsolicited management frame.
Troubleshooting StepsIn a Ruckus AP Support File, note the disconnect reason cited for the particular disconnect in question, for example:
Mar 23 08:54:21 RuckusAP-kla daemon.info hostapd: @@204,clientDisconnect,"apMac"="xx:xx:xx:xx:xx:xx","clientMac"="64:76:ba:98:27:de","ssid"="MySSID",
"bssid"="54:3d:37:d8:9c:a8","wlanId"="49","tenantUUID"="839f87c6-d116-497e-afce-aa8157abd30c",
"apName"="RuckusAP-kla","apLocation"="My Test","clientIP"="10.2.12.2","vlanId"="100",
"radio"="b/g/n","encryption"="None","hostname"="macbookair","firstAuth"="1427100759",
"associationTime"="1427100759","ipAssignTime"="1427100766","disconnectTime"="1427100861",
"sessionDuration"="102","disconnectReason"="8","rxFrames"="305","rxBytes"="21118","txFrames"="85",
"txBytes"="13640","peakRx"="19934","peakTx"="13640","rssi"="25","receivedSignalStrength"="-69",
"Instantaneous rssi"="17","Xput"="0"
In this example, the disconnect was issued due to the sending station leaving (or having left) the BSS (reason code 8):
ResolutionWhen an Access Point (AP) disconnects a UE, according
to the 802.11 standard, it must provide a reason code for why this
event took place. Below is a table of the reason code numbers and their
associated descriptions.

Outside of the above, what Firmware are you running and how do you have you WLAN configured?
Also please note that just because you see something in the log, does not make it an issue.
I would start with the approach of are you experiencing any connectivity issues (other than what you see in a log), if so then i would start to look at each of the mac addresses that are having the issues
Note: Reason codes are not all bad and Reason Code 8 in my eyes is one of these, as is Reason Code 4.