Sorry for not getting back earlier.

I booked through the powetools script from ITA matrix that paul21 has listed above.
I believe it was the UK site (or at least UK point of sale) as i was billed in GBP.

However Austrian did not confirm the first leg of the ticket so after a couple of calls to both Austrian (where the guy on the phone was amused and confused on how I booked this itinerary) and DL who could not see any availability on their systems for the flight I was booked I was given the option of some other reroutings/times for that first leg.

None of the options suited me so I ended up cancelling the ticket thinking that I could book it either by calling Austrian/United/TAs/OTAs but the fare bucket I was booked was not available for sale by Austrian!! The available fare buckets were pricing at a much higher price so I am looking into alternative options.

So now trying to find alternative routes.