Telerik Data Access 2015 Q1 is the last release that includes rich Visual Studio integration and Visual Designer. Here
is the official announcement with a bit more details.
If you update to any version of the product (via Telerik Control panel or any other installer) you will lose the ability to work with .RLINQ
models. Our suggested approach
is to migrate your code to Code-Only mapping using our NuGet packages
(please make sure that you have 2015 Q1 installed before starting the steps outlined in the migration blog post).
If you would rather not put extra effort into migrating you are welcome to continue using 2015 Q1 release, but you should make sure not to update your installation. One caveat of working with 2015 Q1 release is that it support Visual Studio up to 2013 version.
If you have any further questions, or have trouble resuming your development activities, do not hesitate to contact us.
Check out the latest announcement
about Telerik Data Access vNext as a powerful framework
able to solve core development problems.