Sometimes the Gospels have explicit time-markers. Sometimes they have particles that simply indicate a transition from one scene to the next–without indicating the duration of the interval, or whether that even comes later.
Sometimes there's an intrinsic temporal sequence. The arrest of Jesus precedes his trial, which precedes his crucifixion, which precedes his burial, which precedes his resurrection, which precedes his ascension. Even if there were no time-markers to indicate what's sooner in relation to what's later, it would be self-evident.
But in many cases, all we have is a narrative sequence, which may or may not track a chronological sequence. So what should the reader expect?
One issue is how we envision the process of composition. For instance, do we think the author sat down and manually wrote out the Gospel? If so, that would be a somewhat laborious process. How much would he write at a sitting? Would he write a scene, take a break, then pick up where he left off a day or so later?
Another question is whether he had a mental outline of what he intended to include, and in what order. How much did he have planned out in advance?
But here's a different consideration: suppose, instead of writing it out by hand, he dictated his Gospel to a scribe. That involves a different psychological process. When you tell one or more anecdotes about your life, you generally relay them in the order that you remember them rather than the order in which they occurred.
Think about how old folks reminisce. If you ask them what it was like growing up, they don't proceed in a linear fashion. Rather, they string together the most memorable events growing up–often in no particular order. I daresay we have many memories that we can't place in a relative chronology.
Indeed, this tends to be free association, where one memory triggers a related memory. Commentators often talk about narrative strategy and topical arrangement. But how much of that is actually mnemonic rather than literary?
Suppose John dictated his Gospel to a scribe. Suppose that took place over the course of several weeks. Presumably, John thinks about what he's going to tell the scribe today. He consciously summons his memories of Jesus. Mental images of things that happened at a particular time and place.
No doubt John wants his memoir of Jesus to have some structure and directionality. Have a beginning, middle, and end.
Still, if the Fourth Gospel is a transcript of his recollections of Jesus, there's no antecedent reason we'd expect it to be rigorously chronological. Memories of people you knew pop into your awareness without any temporal sequence.
If the Fourth Gospel is oral history committed to writing, I doubt John was chronologically self-conscious as he tells an anecdote. Presumably, he's not thinking about where the next anecdote should go at the time he's recalling something Jesus said or did. Unlike writing, it's easier to lose your train of thought when dictating unless you concentrate on one thing at a time. If you interrupt an older person who's telling an anecdote, they may well forget where they were. They lose the thread.
Incidentally, this may explain the "epilogue" to John's Gospel. His Gospel seems to have two endings. It apparently ends with chap. 20. Yet that's followed by chap. 21. If, however, John was dictating his Gospel, then that "afterthought" is very understandable. That's how people remember things. They don't have everything before their eyes. Rather, their mind jumps from one recollection to another.
Likewise, that may explain the temple cleansing in Jn 2. Jesus either cleansed the temple once or twice. We can't say for sure. All we have to go by are the Gospels, and they don't number the temple cleansing(s). It's possible that he did so twice. Or it's possible that this was one event, which John's Gospel records in chap 2 because he remembered it on the day he dictated that section of the Gospel.