Originally Posted by
JALPak
Your assumption is wrong, at least not with 06 or any of the A350-1000 so far.
https://www.aviationwire.jp/archives/309890
They may not need the full 3 weeks but it doesn’t hurt to be conservative and move up the schedule if needed. It’s not JAL’s problem per se if someone intentionally booked an inaugural flight and missed it because the dates are moved up

From reading that page using Google translate it doesn’t seem to mention anything about seat installation? I thought generally they are installed in TLS for most airlines? Looks great in the photos! I didn’t realise maintenance would be required on a new aircraft.