The latest sdkmanager (sdkmanager_1.6.1-8175_amd64.deb) and the one recommended for 4.3 (https://developer.nvidia.com/jetpack-43-archive) does not allow to get 4.3 Jetpack only 4.4 and up and 3.x and lower,
Need 4.3 for J121 Auvidea board, because @AuvideaSupport made patches only for 4.3 Jetpack.
Thanks.