I think the order in which someone is going through the buyer journey is less important than what they're seeing at each stage. We map content to each stage in the buyer journey (using the SiriusDecisions framework although others are good), as well as to different ICPs, and then just listen to the buyer to know where they're at. The example you gave we would look at as being signals for where someone is in their journey more so than an actual stage in the journey, and you can use those signals to give them content that actually moves them forward towards making a decision. If someone requests a demo first or does the free trial first, they're probably pretty close to each other in the buyer journey and can see very similar content, it would just differ based on what ICP group they fall into.
