Just watched the movie (spoiler)
Just came back from watching the movie!
The first around 80minutes was the season 1 recap but it did have some extra shots that werent in the anime series but not too much. The last 40~50minutes was the first 2 ep of season 2 and it covers the whole red gate ark (sorry if this is a spoiler). It was definitely a faster pace than the manhwa but didnt feel rushed as it did contain all of the core moments and nothing felt skipped out. The animation quality was overall pretty good. A1 did an amazing job once again.
After the movie I got these things called ttt (that's the ticket) which they give out to ppl who watched the movie in cgv theaters in Korea.
And yes the movie did contain the Iron being weird moment