And this is why I fully expect it to make its own discoveries. And I understand the disappointment in JWST rehashing what has already been shown instead of bringing something shiny new to the table. But to this, i say it showcases that it confirms what Hubble saw and shows that its images are just as clear before going forward to see what has not been before.Just adding to your excellent responses.
JWST took 12.5 hours to take the deep field image. https://www.nasa.gov/image-feature/goddard/2022/nasa-s-webb-delivers-deepest-infrared-image-of-universe-yet
Also, note that JWST was not focused at 13.1 billion light years, but 4.6 billion light years. They were duplicating an image Hubble had taken ( conjecture: because it showcases the abilities of JWST.)
The main issue with Hubble is that it orbits the Earth, where JWST orbits the sun. Earth orbit means Hubble didn't have a long exposure time on a specific area of the universe during any particular session, so multiple sessions were required. On the other hand, JWST has a continuous view that could last for days, but it is orbiting the sun rather than Earth (and it is orbiting arouind the LaGrange point) so a particular view might need also to take years to get. But it can do a ton of other stuff in the mean time.
:: edit: there was a mess in the second last sentence... I was distracted by what turned out to be a shiny nut.