For future readers, my issue was related to IPsec being used with CARP interfaces. This has been patched and in the next release cycle.
https://github.com/opnsense/core/commit/4080345a597fbc55c02256996f7ba3ccee78ae49
https://github.com/opnsense/core/commit/4080345a597fbc55c02256996f7ba3ccee78ae49