The update is being rolled out via OTA in a phased manner. Currently the update is being rolled out in India and we are expecting it to go global in the coming days. This is a major update which brings the latest ColorOS 7 to the device. The OTA Update size is around 300MB. If you own the device you can manually check for the update.
Manual update guide
Now, there is no download link available at this time. So, all the interested users may have to wait for the OTA update notice. Additionally, users can manually check for the OTA update via Settings – Software updates – Download updates manually. If available, you can download and install the latest OTA update. Source