The links below provide information and technical guidance for software developers and transmitters who are interested in developing software for AIR for Tax Year 2020. Included are links to Known Issues, Form to Schema Crosswalks, XML Schemas, and Business Rules. Tax year 2020 documents: Known issues During production, the Known Issues and Solutions document provides notifications of problems identified, workarounds and date of resolution. Known Issues and Solutions PDF: (05/04/2021) Form to schema crosswalks The Crosswalks provide a line by line reference of the schema elements, patterns and descriptions. They should be used only as a guide when developing software. Always refer to the actual schema files in the link below when developing software. Updated 9/10/2020 Form 1094-B Form to Schema Crosswalk PDF Form 1094-C Form to Schema Crosswalk PDF Form 1095-B Form to Schema Crosswalk PDF Form 1095-C Form to Schema Crosswalk PDF XML schemas, business rules and release memo Special attention should be paid to the projected start and end dates for AIR Assurance Testing System (AATS) and Production. Throughout the year updated versions of these files may be posted. Each version will show the start date and end date for both AATS and Production when that file version should be used. Multiple versions of these documents may be in use at the same time. Included within the schema file is a DIFF File showing differences from the previous version. Tax year 2020 Forms 1094-B, 1094-C, 1095-B, and 1095-C Version Date Posted AATS Dates Production Dates TY2020v1.1 Note: This version of 1.1 includes updated Business Rules. 09/09/2021 Start Date: TBD End Date: TBD Start Date: TBD End Date: TBD TY2020v1.1 Note: This version of 1.1 includes updated Schema. 10/08/2020 Start Date: 11/02/2020 End Date: TBD Start Date: 01/14/2021 End Date: TBD TY2020v1.0 09/10/2020 Start Date: TBD End Date: TBD Start Date: TBD End Date: TBD