Hmmm... People's Viennaline definitely has an IATA code of PE, but Planespotters and Wikipedia both have their ICAO code as PEO, which still seems to be assigned to Libyan airline Petro Air, whose logo we have, and whose website is unsurprisingly dead at the moment.
No offence, Ian, but I'm going for PEO - I'd move our existing PEO to a safe place first, in case you're right ;-)
Rod