If you build calendars on the web and abbreviate the days in the column headings (you do use column headings, yeah?), this is how it sounds to a JAWS user. Sorry, your browser doesn’t support embedded videos, but don’t worry, you can download it. The caption file is also available…

This is a helpful article on how to create accessible calendar tables with abbreviations. It highlights how to use the aria-hidden when using an abbreviation. It also notes that the <abbr> tag is only recognized by VoiceOver on Macs. There are a lot of helpful examples provided.