The quote on the left is often falsely attributed to Martin Luther or Martin Luther King, and in the original quote the blank space is "apple". The quote means that "even if you are not going to reap the benefits of an action you must still do it because it is the right thing to do". It is quite fitting for ATEEZ, who liberated World Z of Z's oppressive regime even though it was not their own world and couldn't enjoy the result because they were immediately sent back to World A.
The quote on the right is from William Tell. He was a rebel against a tyrannical local leader in Switzerland. When he went against the tyrant, he was forced to shoot an apple on top of his son's head with an arrow to regain his freedom. He succeeds but since he reveals his intention to kill the tyrant he is still captured. While he was being taken to the dungeon with a boat a storm breaks out. Fearing the boat would sink, the soldiers free Tell to save the situation, but he sails into rocks and escapes.
Both quotes are attributed to revolutionary figures, which may mean we are going back to our World Z storyline.
The blue poster has a lot to unpack. Starting with the burning, torn down buildings, they remind me so much of Halazia.
This isn't the only Halazia connection. In the poster, among the clouds on the top there is a shining ball in the sky. The last time we saw such a thing was in Halazia.
Moving on, we see the guy (probably Yeosang) plant a tree. The tree is planted on red soil, like it was watered with blood for its first water. Visually, we see trees a lot in ATEEZ's videos, like the burning tree in Fireworks and the trees in Crazy Form promotions (one alive and one charred).
In the canon, however, there is one very relevant tree, which is the Sibling Tree, two trees planted for the brothers that died at the Disposal Center merged into one and i think showing the tree planted on their blood is a very interesting image. The tree is important to Yeosang, since at the brothers' funeral, when the tree is planted, he swears their deaths will not be in vain. The tree is in Thunder's headquarters, which is now used as the interim government of the Liberation Zone, where people who don't want to have their emotions artificially controlled live.
In the sky, we see white doves (which are one of the symbols surrounding Yeosang) flying away. This is usually a symbol for broken peace. Putting all these together I have a theory that at one point, when ATEEZ were no longer there, the Liberation Zone and the Control Zone, who decided to coexist through an agreement, broke the peace and started a war. This then lead to the situation we see in Halazia with the city seen in the MV being the Liberation Zone and the people who first waited for Halateez and then turned against them when they didn't come back being the Liberated people.
There is one more detail in this poster which could mean nothing but bothers me a lot, which is the broken waterjar at the bottom. I tried searching for what that symbol could mean and came across this poem:
I am limited with my shallow understanding of symbolist poems and the Mexican history but the poem seems to present themes of exploitative rulers, dreaming of a better world, returning to the origin, and the effects of mankind's greed, war and misery on the earth. Most of these overlap with ATEEZ's themes. Furthermore, we can see some symbols like blue sun, dreamers, waves, answers, and birds that pop up in ATEEZ's art also in this poem. If I am right and this is a relevant thing, then it can reinforce the themes ATEEZ will explore in Golden Hour Part.3 and onwards.
About the second poster, there are 8 people on it. The seven's eyes are blurred and one is aiming with a crossbow. This can mean two things:
a) The people are brainwashed by the government and now target the revolutionaries.
b) As also seen in William Tell, the revolutionaries are forced to risk one of their own.
I like the second a bit more. And in ATEEZ we have a member who is closely associated with apples, planting and trees (credit to @/jonghopedia on twitter for the images below)
Which raises the idea: What if the group will have to risk Jongho in one of their revolutionary acts? This would also give some meaning to the Jongho holding apples image in the Birthday MV which we couldn't find a non-meta explanation for.
If this part follows the William Tell story then maybe the boat part can be recreated in ATEEZ's story as well, which would be fitting since they are pirates.