In a tweet by WABetaInfo, a new WhatsApp for iOS update (2.18.31) includes a the new “Delete for everyone” limit of one hour, eight minutes and 16 seconds long, alongside various bug fixes.
Though WABetaInfo revealed the oddly-specific duration was equal to 2^12 seconds, or 4096 seconds long, the WhatsApp support pages don’t provide any explanation for the time limit.
It was significantly longer than the initial “delete for everyone” feature introduced in October that allowed users to delete messages up to seven minutes after sending.
So far, there was no word on when the update would be rolled out for Android systems.
https://www.thestar.com.my/tech/tech-news/2018/03/13/whatsapp-delete-message-feature-extended-to-one-hour/