Before this round, City were favourites with odds of around 2.4 and Arsenal were just behind at 2.5. But Liverpool were priced very poorly (6.50), Chelsea even worse (26.0). Tomorrow the last game of this round will be played and bookmakers will update the odds for the title. It is very likely that City will no longer be favourites and may even fall to third place.
It's not that bookmakers wait for the current round to end and then update the odds. Bookmakers update the odds regularly.
Currently, the odds for Arsenal to win the title are 2.25 and for Manchester City are 3.
It depends on the bookmakers, the ones where I play only post odds between rounds, until the round is closed there are no odds. Since you are showing current quotes, you could indicate their source, the figures that I cited, I took from sportsbet.io
By the way, your figures don't look real, 2.25 for Arsenal considering that Liverpool is leading? Well, maybe Arsenal is strong, yes, but where is the space for Liverpool and Chelsea with figures of 2.25 and 3?