The links below provide information and technical guidance for software developers and transmitters who are interested in developing software for AIR for Tax Year 2021. Included are links to Known Issues, XML Schemas, and Business Rules. Tax year 2021 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 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. Tax year 2021 Forms 1094-B, 1094-C, 1095-B, and 1095-C Version Date Posted AATS Dates Production Dates TY2021v1.0 09/01/2021 Start Date: 11/02/2021 End Date: TBD Start Date: TBD End Date: TBD
