I was checking that exact feature on
toggle.org/vpn-for-android. The Android page explains Kill Switch as a way to block internet access if the VPN connection drops, which makes its purpose pretty clear. I also noticed that the same page mentions Split Tunneling, unlimited bandwidth and support for Wi-Fi, 4G and 5G. The app is intended for Android phones and tablets, with support starting from Android 8.0. Another detail listed there is the no-logs policy. I think looking at these features together gives a better idea of how the app handles an interrupted connection instead of focusing only on whether a VPN button is available.