[Nebula] - Client list - More than one device with same IPv4 - Tailscale network

Hello everyone,
I've configured a Tailscale VPN via my USG Flex 200HP firewall (my firewall act also as exit node for the Tailscale network).

Currently I use my iPhone, connected into the Tailscale network using the firewall exit node and into the Nebula portal, under the device list, I see a lot of device with different MAC Address but same IPv4 address; also, all these devices are always offline and with the "Last seen" property as a near minutes between each other (for example the first devices have today @ 2:32PM, the second today @ 3:18PM, the third today @ 4:08PM)

Also, seems that in some cases the MAC Address is the same (as example: 40:00:3F:xx:xx:F4), and in other cases some devices are "really" connected using the same IPv4 Address with different MAC

Can be that the Tailscale network "change" MAC Address to connected devices every "XX minutes"? I've more or less "100+ devices" in that state.

Can you "filter" or exclude those devices from the client list?

Thank you