The timeline tells a different story. @Mrbluntzy's topic was April 18, 2025, 11:37:22 AM. You say you received the notification, copied the topic, something happened that made you distracted and pasted it on April 18, 2025, 11:48:11 AM but you have this reply.
Let me assist you in understanding what I understand from his post.
Of course, he posted it later, and this is why it is considered plagiarism.
According to him,
He was about to reply to Mrbluntzy's topic, which is why he copied part of his thread to quote him, but he got a notification, and that was from another thread. He was writing there and got distracted somehow (I'm not sure what level of distraction it was). He pasted the text in his clipboard and posted it, thinking he was replying to Mrbluntzy's topic. Sometimes, we mess up when quoting others. Especially when we are on smartphones.
I also want to believe this is an honest mistake if he has no plagiarism history. Why would someone copy a post that was posted only eleven minutes ago to ruin their high-ranking forum account?