GPT-5.5 Thinking shows 5.4 label in ChatGPT

Reddit users are reporting a confusing routing or labeling issue where a ChatGPT 5.5 Thinking selection appears to produce responses identified as 5.4 Thinking instead. The thread also describes blank-screen behavior in the app that resolves only after reopening the chat, which points to a client or backend routing bug rather than a meaningful model downgrade.