After more than 15 years covering everything Apple, it’s with a heavy heart we announce that we will no longer be publishing new content on iMore and the iMore forums will be closing as of November 1st, 2024.
As stated in another thread, I doubt you'll be able to upgrade the iPad 3 to the latest iOS version, even via jailbreak, but since I don't jailbreak my devices, I could be wrong. Hopefully, those who do jailbreak can verify my claim soon.