Once you verify your number, WhatsApp servers will immediately detect your old version. Within minutes to hours, you will likely see a red banner: "This version of WhatsApp is no longer supported. Please update to continue." This is because Meta disables older protocols.
WhatsApp Business has a lighter footprint and sometimes supports older Android versions longer than the main app. Search Uptodown for "WhatsApp Business 2.19.352" – that often works on KitKat. whatsapp 4.4 2 apk download old version uptodown
