There are some times that plate/inscription/corner blocks can be confusing to collectors of Canadian postage stamps, especially for those issues from 1958 on wards. Canada # 375 and # 376 were issued with no plate block inscriptions at all along with # 337 (pl. 10), 338 (pl. 10), # 340 (pl. 13, 14), 341 (pl. 14). This occurred because the post office department wanted to get rid of plate block inscriptions on stamps because collectors looking for these were disrupting regular retail post office operations with their demands for plate blocks.
However, after many collector complaints, plate blocks would become available again to collectors, but only through the
Canada Post philatelic agency. All post offices would only carry panes that had the inscriptions trimmed off. Some collectors still buy panes from their local post office or from others with trimmed off inscriptions (field stock) not realizing that panes with full inscriptions (philatelic stock) are or were available from the philatelic agency since full inscriptions are more desirable to collect for stamp collectors.