In version 2.1.0, Peer-to-Peer uses the block editor for campaign pages. You can add any content that is available in a block. Any countdown timer plugin that provides a block should work. Update your Peer-to-Peer add-on to the latest version to try it out.

Keep the votes and comments coming, here! We're listening. Next development cycle will likely include some time devoted to Peer-to-Peer, but that' determined by how much interest we have in various features!