An upcoming WhatsApp update will drop support for older iPhones, according to WABetaInfo portal (which is well-known for its accurate insiders on new developments, including test versions and messengers).
This means that older iPhones, namely iPhone 5, and iPhone 5C will no longer be supported.
In addition, WhatsApp will no longer be supported on the versions iOS 10 and 11 from the 24th of October 2022. To run on the latest iOS update, go to Settings > General, then tap Software Update to get the latest iOS version.
As for Android, the device must be running Android 4.1 or above to be supported by WhatsApp.
In other related news, Apple is also expected to drop support for its iPhone 6 series as well as the original iPhone SE.