ChatGPT and Wolfram Alpha confirmed to me that it's about 37 days, which is 888 hours, not 88 :)
Wolfram Alpha: https://www.wolframalpha.com/input?i=400tb+at+1gbps ChatGPT: https://chatgpt.com/share/4ddd464a-dabd-4c12-9cc4-e8271a51a6...
(ChatGPT did a great job at breaking down the problem)