Originally Posted by
s1362083
One further question, is the interlining blocked by the IT system when it is ineligible or is it at the agent's discretion? If the latter then perhaps I can ask for written confirmation when booking so I can go to the airport fairly confident that the agent would be forced to through check.
Why on earth would they give you this? As mentioned, the option is there to put it on one ticket, it just costs more - much of which is APD which BA would very dubiously be helping you to avoid if they did this.