Hi,
In this case, presumably the "Alternate" Collection Step would have been triggered multiple times for a given Contract Account.
If this is the case, you could look up the Dunning history for non-reversed (or reversed & non-reversed, depending on your business criteria/process) table via a DBLOOKUP Expression in the BRF.
You would specify the Contract Account and Alternative Collection step as look up criteria, and return a value as COUNT. You may then influence the next Collection Step based on the value retrieved.
I hope this helps.
Regards,
Ivor