Hi Roland,
What you are describing is normal B1i behavior.
Even when the step is running on receiver side and outbound channel is B1 call, there will be two separate transactions: OUT_B1 will run two times with first round to go through vBIU and second to conduct out B1 call. So when out B1 call is incorrect, the first OUT_B1 transaction will not be rolled back.
If you want all operations to be done in the same transaction you will need to do all B1 calls inside the
scenario steps and have Outbound void.
Regards,
Trinidad.