I did not realise you could get to the main Liverpool St. gateline when coming of the Elizabeth line. I thought the only exit was the one shown in #30.Which gateline are you referring to here? There's a small gateline at the Broadgate side (within the Moorgate footprint), but otherwise you walk over to the "main" Liverpool Street LU gateline to get to the mainline terminus (through which you'd have to go through gatelines again to get to P1-17).