We are currently reviewing an ESTRY/TUFLOW model and the question has come up when should a modeller be using 2d_bc_hx, or 2d_bc_hxe and 2d_bc_hxi. As on this occasion the modeller has chosen to use 2d_bc_hxi thorough out the model and now has several hundred "Check 2231" messages, we know this occurs because there are no zpt points on some of the HXi lines. So the questions we have are: When do we use these different hx types?What the benefits of each type? Thanks Fil