RED tunnel establishment failure

Hi guys, first time poster, had to come here as I'm not super familiar with the Sophos RED tunnels.

We are running multiple sites through the same ISP, each site has the same link that breaks out via the same hosted firewall.
All of these sites have the same breakout public IP.

Previously with this same setup, we established a tunnel from each site to our central firewall, thus our device would see multiple tunnels come in with the same source IP but different ID's. Now the tunnels are flapping.

Can the Sophos devices handle multiple tunnels with the same source IP, or will there be issues with that?

Thanks