Lewis on updating and self-location
A lot has been written in the last 10 years or so on updating self-locating beliefs, mostly in the context of the Sleeping Beauty problem. One thing almost all of these papers have in common is that they quote Lewis's remark in "Attitudes de dicto and de se" (1979, p.534), where he says:
it is interesting to ask what happens to decision theory if we take all attitudes as de se. Answer: very little. We replace the space of worlds by the space of centered worlds, or by the space of all inhabitants of worlds. All else is just as before.
This is supposed to imply that Lewis took standard conditionalisation to be the correct update rule for self-locating belief.
Now I'm not sure exactly what Lewis thought about updating self-locating beliefs, but this interpretation seems a bit quick, for various reasons.
First, the fact that standard conditionalisation does not work well with self-locating contents is rather obvious, and Lewis wasn't stupid.
Second, Lewis talks about decision theory in that quote, and it is not clear that rules for updating belief are an essential part of decision theory. Jeffrey, for example, is quite ambivalent about such rules, even about "Jeffrey conditionalisation". (However, Lewis does mention a bit further down in "Attitudes" that one thing that stays the same if one moves to centered worlds is that "probabilities change under the impact of [...] perception".)
Third, even if Lewis considered rules for belief dynamics to be part of decision theory, it is not clear that he thought the only such rule is standard conditionalisation. This was quite controversial in the late 70s, and at various places Lewis himself is skeptical about the claim (and not only because of centering). See e.g. the preface to "Why conditionalize?".
Fourth, there are other places where Lewis mentions updating and self-location, and where he says a bit more. The most relevant is probably footnote 6 in "Desire as Belief II" (1996, p.309f.), which goes as follows:
I assume here that one way to revise credences is by conditionalizing, and that DAB [Desire as Belief] will continue to hold after any such revision; I do not assume that credences may never be revised in any other way. Nor, pace Graham Oddie, was it "a fundamental assumption" (1994, p.466) of my previous refutation that revisions of credence must invariably go by conditionalizing; or even that they must invariably go by the sort of generalized conditionalizing that Richard Jeffrey has described under the name of "probability kinematics". Maybe Oddie is right that there are other ways for credences to be revised, at least when they are the credences of tensed propositions. (Before I turned out the light, I saw that it was just minutes before midnight. In the course of a long and sleepless night, I undergo a redistribution of credence from the proposition that it is now before midnight to the proposition it is now after midnight. It is far from obvious that this revision goes by probability kinematics, let alone by conditionalizing.) But the fact, if fact it be, does nothing to rescue DAB frome either my present or my previous refutation.
So Lewis was certainly aware of the problem at least in the nineties.
None of this is proof that he didn't believe in 1979 that standard conditionalisation is the (only) correct rule for updating self-locating beliefs. But the textual evidence that he ever held this view is meager.
Just for the record.