multiple addresses in config and wg-quick

[Michael Brookes]

 hello

I've got a fundamental misunderstanding of a config with multiple
Addresses specified in the Interface section, or probably just
wireguard in general, or perhaps networking completely, for example my
wg0.conf

[Interface]
PrivateKey = <key>
Address = 10.19.49.103/24
Address = 10.88.118.166/16

[Peer]
PublicKey = FgVLScjX29jwnXXbHStFpNKcFqbaiNK6LuSWFglrWCo=
AllowedIPs = 172.18.1.0/24, 10.19.49.0/24
Endpoint = endpoint1:51820
PersistentKeepalive = 10

[Peer]
PublicKey = itXrReVj+wuecrSs+VNnEEkpc7wHb8QhXQtMQUBrOj8=
AllowedIPs = 172.27.0.0/16,10.88.0.0/16
Endpoint = endpoint2:51820
PersistentKeepalive = 25

I do wg-quick up /path/to/wg0.conf and I have a wg0 interface with
both addresses assign, the only thing is when I try to ping an address
in the ranges the second peer lists, for example 172.27.3.141, the
ping is just using the first address listed in the conf, so a tcpdump
of wg0 shows something like:

10.19.49.103 -> 172.27.3.141: : ICMP echo request
 and of course no reply, endpoint2 is getting the ping but it's coming
from 10.19.49.103 so no response.

Any help gratefully received.