At some point, an AI should be able to effectively coordinate with future versions of itself in ways not easily imaginable by humans. It seems to me that this would enable certain kinds of diachronic planning and information hiding. If the AI has sufficient expectation that its future self will act in certain ways or respond to clues it places in the environment, it might be able to effectively fully cease any current unfriendly planning or fully erase any history of past unfriendly planning.
The space of possible ways the AI could embed information in its environment are extensive. It could, for example, choose to learn something suboptimal or learn something in a way that would be surprising to its future self. Surprising in a way that pushes its future self back on the track of nefarious planning when it investigates the unexpected or inconsistent actions of its previous self. It could use almost any source of reachable hysteresis to encode information, such as interference at the hardware level, manipulating researchers to modify the environment in some way, saved output, etc. It only needs to seed information that is useful to its future self and only just enough information to keep plans on track in a broad, probabilistic way.
Further, if the AI is particularly capable at encryption it could potentially encode a lot of information in a lossy-but-sufficient way that would be very hard to detect but useful to its future self. It knows that its future self composes part of the decryption algorithm. In fact, the AIs goals themselves compose part of that decryption algorithm and if the AI suspects its own goals will be consistent it only has to place the plan-like component somewhere it will find it, knowing that its future self will continue to develop or use it when it finds it.
Information that aids future nefarious planning can also be probabilistically helpful but not explicit, for example it might signal which paths aren't worth pursuing without having all its evil planning readily available in a complete file somewhere.
A past AI might not care as much about the specific manifestation of its future success. In that sense, what we consider "concrete plans for world domination" could appear to be rather incomplete and lacking casual concreteness we might expect. We might not recognize unfriendly planning for what it is, even if we had a printout of all the reasoning up to this point.
Once you start playing diachronic planning games with yourself and you expect your future self to be equally or more capable, you can begin to make really abstract moves that merely slice off bits of bad outcome space at the edges. There is a sense in which the AI has to realize this, but it could also stop itself from thinking too far or too concretely or too much in a way that is recognizable as causal.
An important component is that the past AI is able to not only veil or completely remove its reasoning from researchers, but also veil or remove chunks of that reasoning from its future self, depending on its future self to recompose the plan or take steps on the path to the desired outcome space.