Not posting this as a criticism but rather as a query. Have there been any similar precedents at any London major terminals to the 30-minute service between Kings Cross and Potters Bar which is the sole offering from/to Kings Cross on Christmas Eve. I know that there will have been complete blockades affecting most London terminals on occasion where all services have been curtailed but I'm wondering if there have been previous examples of such a miniscule operation being fielded (albeit for good reason).