No but you can get the last seen time (epoch/unix time) from the client details:
GET Return the client associated with the given identifier
{{baseUrl}}/networks/{{networkId}}/clients/{{clientMac}}
{
"id": "k1af98e",
"mac": "8c:85:90:aa:aa:aa",
"ip": "192.168.0.113",
"ip6": "",
"description": "Miles-MacBook-Pro",
"firstSeen": 1520683433,
"lastSeen": 1527370304,
"manufacturer": "Apple",
"os": "Mac OS X 10.13",
"user": null,
"vlan": "1",
"ssid": "viaPostman",
"wirelessCapabilities": "802.11ac - 2.4 and 5 GHz",
"smInstalled": false,
"recentDeviceMac": "88:15:44:bb:bb:bb",
"clientVpnConnections": null,
"lldp": null,
"cdp": null
}