I’ve found that Roon ignores indefinite articles (A and An) on an inconsistent basis. Better known artists/groups such as ‘A Guy Called Gerald’, ‘A Tribe Called Quest’, ‘A Certain Ratio’ and ‘A Taste Of Honey’ get filed appropriately while lesser known artists such as ‘A Minor Forest’ and ‘A Grave With No Name’ get filled under the letter A.
Roon seems to ignores definite articles in multiple languages (The (English), Los (Spanish)) on a consistent basis.
The poor solution is to create a new Album Artist with the letter A missing entirely or with a comma A at the end of the name. Not a very elegant solution in my estimation