The expression once every Preston Guild used to be widely used to mean very infrequently, as in…

The expression once every Preston Guild used to be widely
used to mean very infrequently, as in once in a blue moon. It refers to an
event which has been held in the northern English city of Preston every 20 years
since 1542 (with a single exception during the Second World War) and
irregularly before that since at least 1328. The website for the event notes:
Held only once every twenty years, the Guild plays an important role in the
development of Preston as a thriving and important Lancashire city. The
changing times mean that each Guild has its own identity but shares a heritage
of

The expression once every Preston Guild used to be widely
used to mean very infrequently, as in once in a blue moon. It refers to an
event which has been held in the northern English city of Preston every 20 years
since 1542 (with a single exception during the Second World War) and
irregularly before that since at least 1328. The website for the event notes:
Held only once every twenty years, the Guild plays an important role in the
development of Preston as a thriving and important Lancashire city. The
changing times mean that each Guild has its own identity but shares a heritage
of over 800 years. Its origins lie in the time when each trade guild held and
protected a monopoly on the right to trade. The event thus was in part a trade
fair, but also in part a celebration. Todays event has a wider remit, and,
because of its infrequency, it plays a part in retaining links with the
diaspora of erstwhile Preston citizens. Preston Guild 2012 retained key
elements that have characterised previous Guilds, such as the formal
proclamations, the holding of a Guild Court, formal processions and church
services, and a Mayoral Ball. For the first time, in 2012, ceremonies included
the admission of Honorary Burgesses to the Guilds. Nominations for this title
were sought from those who have contributed to life in Preston. Perhaps
surprisingly in the 21st century, those who are elected will pass their status
as a burgess on to their sons and daughters. Throughout the summer of 2012 a
series of less formal events took place. These included cultural events, such
as a Mela (a festival celebrating South East Asian culture) and a Caribbean
Festival, and more traditional events such as a carnival King and Queen
competition and the Annual Whit Fair. Sportsrelated events had a prominence in
2012, including an Olympic Torch Relay event, and were related to the fact that
Preston was the designated UK European City of Sport in 2012. There was also an
emphasis on encouraging the people of Preston to organise their own community
events and street parties, an event planning toolkit being available from the
organisers of the Guild. Preston citizens could volunteer as Guilders, and
participate in the four major processions: the Trades Procession, the Churches
Procession, the Community Procession and the Torchlight Procession. The
organisers were a team called the Guild 2012 Team who operated within Preston
City Council.