Getting Slack Thread id within Automation Formula

Hiya, thanks in advance for any pointers.
We have a successful automation that creates a new thread in a Slack channel when an incident manager clicks a button in Fibery (Button A)
We’d like to have subsequent actions (Action B) that update that thread with additional information. It seems that the “Send Message to Channel” action can take a thread ID so that a message can be posted as an update, but the issue is getting that ID.
I can’t seem to figure out how to get the Thread ID for the thread created in Button A so that I can store it so that it can be used in Action B. Does anyone have any pointers?

At the moment, it’s not possible to get the ID of the message that was sent in a previous action. The message ID will become available the next time you sync the message data in the slack integration:

Thank you Chr1sG, appreciate the confirmation!