Birth was recorded in Toxteth Park in 1892. (Incorporated into Liverpool 1895.)
His death was recorded in Montréal, 1955.

Verification:

• Birth - online copies of birth registration, baptismal records, enlistment declarations given in his own hand.
• Death - online newspaper archive of obituary, provincial registration of death records, public online grave location service.

This was a volunteer Sunday choir at St Peter's Church, used as a pro-Cathedral, a temporary home for the young diocese; it is not regarded as "Liverpool Cathedral" by the Liverpool Cathedral archivists. It did not have a choir school, or a program of daily evensong.

Press clippings of the era indisputably demonstrate that young Coller is active in greater Liverpool through the age of fourteen, not in a residential Oxford choir school. The archivist of Christ Church Cathedral Oxford has found no record of him in their registers nor in their financial records. The confusion may arise because there are other contemporaneous individuals named Percy (not E.B.) Coller, including one born the same year on the correct side of England, and particularly a Percy Collen from the Oxbridge area who some years before was a lay clerk of the University, not Cathedral, choir.

He was not sub-organist at Liverpool Cathedral according to the Cathedral's archivists, and at age fifteen, there wasn't even a Liverpool Cathedral for him to be sub-organist of; the diocese was using a local church serving as a pro-cathedral and Coller was a student at an exam-level high school. It would be yet another three years before the newly finished Lady Chapel was consecrated, the first phase of the now-complete Cathedral, a year in which he appears on a passenger manifest as arriving in Philadelpha.

He began study in architecture but did not complete a degree. Following the first world war, he started a program for a B. Arch. at the University of Liverpool, making use of the government benefit covering full or partial fees for returning servicemen. He withdrew after 1½ years, according to ULIV archivists; their search of later years confirms he did not receive a degree prior to his emigration to Montréal. At the time of his withdrawal, he was 29 years of age, had been married two years, and his second child had just been born.

In 1924, a passenger manifest reveals Coller returning from Africa, giving the Gold Coast as his address for a period of 'at least one year,' and listing his inbound return address as "c/o Canon David Dorrity." This was an uncle, an older sibling of his mother Susan Dorrity, and the celebrated rector of St Ann's Manchester and non-residentiary Canon of Manchester Cathedral. Canon Dorrity was active in an African Missionary society, a noted preacher, chaplain of two schools for children with special needs, and a social activist. It is reasonable to infer that after the war, following his father's passing, Coller and his kin found a patron in Canon Dorrity. Coller stayed one last year in England, then sailed to Montréal - declaring himself a "professional musician" on the manifest - his passage sponsored by  a Canadian business magnate. His years in Liverpool were now over, and he took up his post-war career in the Montréal enclave known as the Town of Mount Royal, at St. Peter's Church.