delete firewall state after delay after reboot based on criteria

[CanadaGuy]

When I reboot my opnsense box, my Cisco ATA seems to have issues with opnsense, in that the ATA somehow gets a stuck state in the firewall and the state never times out (after days for example) or otherwise clears. Once I delete that stuck state, the ATA connects and it is good to the next reboot.

1) Can someone describe or point me to how I would script the removal of a firewall state based on source IP (and maybe destination port)
2) Can someone describe how I might apply this to run after a delay after opnsense starts up?

I do believe it is related to FreeBSD or opnsense, as I have a similar issue (I think) with wireguard tunnels that run on a host behind opnsense. I don't have the skills or knowledge to debug this myself, but would be open to work with someone to resolve the root issue. I did note have these issues with these exact devices behind my UI EdgeRouter.