Thanks for your prompt reply.
Unfortunately it did not work in the way I was hoping.
The outflow reach creates the hydrograph as expected, and the Inflow uses this hydrograph as expected.
Though I was hoping the outflow values produced (D) would be used as the upstream catchment flow (Q). Instead the Q from the outflow reach is also used as the Q for the inflow reach which I suppose in hindsight is expected.
Essentially, I want to redirect a flow, up to a certain value (i.e. being the assumed pipe capacity) so piped flow goes one direction, remainder of the flow another direction.
I also tried using a Formula and Table option for the Inflow maintaining the hydrograph identifier assuming it would continue to read the Q for purposes of calculating D (no luck)
Any suggestions on how this is best handled would be appreciated.