Fortigate Ha cluster three member direct ha question

Dear Community,


I have cluster on siteA with primary and secondary. Their ha interface connected with a direct cable. Also there are x1 ports in the hbdev configuration via a switch. Now I would like to add a third fortigate to the cluster but this is on siteB. The x1 ports are connected via switch on L2 between siteA and siteB. While the hb interfaces are only connected on siteA devices (primary and secondary) with direct cable without switch. Because the hbdv setting mirroring between the primary and secondary units, I think the x1 should be the higher priority in the hbdv setting. But what should I do with the dircet ha config? Should I have to remove it? Or should it remain in the hbdev config with lower priority as a “backup between devices on siteA”? In this last case the remote siteB new fortigate (subordinate secondary) will see its hb interface as permanent dead, and will ignore it?

thank you