Did early analytic philosophers reject metaphysics? Or did this rejection only come about with the rise of the logical positivists? By early analytic philosophers i mean, Frege, Russell, and Moore, and any other analytic philosopher before the logical positivists.
Early analytic philosophy did reject "metaphysics." But it's important to understand why they would be motivated to do so. The answer for English-speaking ones is the Oxford Hegelians. In other words, Hegel (or at least an interpretation of it) was the dominant philosophy in the English-speaking world in the 19th century. One of the humorous details of how this all works out is that McTaggart, now remembered for A-theory and B-theory of time was actually a Hegelian who rejected both in favor of C-theory: that time is an illusion.
More generally, these philosophers were arguing against a background of highly convoluted philosophy in general. The project of metaphysics and epistemology in their modern forms (here modern as opposed to contemporary) was largely getting out of hand to the point where there are dogmatic competing systems that seem broken. Thus, two main responses evolved: positivism, etc., that rejected metaphysics and phenomenology that side-stepped epistemological questions.
The rejection of this sort of idea of metaphysics by Russell is equally forceful with the later rejections by the logical positivists (though it must be admitted he accepts metaphysics under certain definitions). I don't have specific data on Moore and Frege. But my sense is that Moore's project in ethics is compatible with a denial of metaphysics but does not require it.
It goes back earlier than that, to the Vienna Circle in Austria that critiqued 'metaphysics' as empty posturing; their target then was Hegelianism.
This reaction appears in various guises in Philosophy. For example Kants Critical Philosophy reacted against the Dogmatic metaphysics of Aristotelianism - exemplified say by the Emanationist theory of Spinoza or the Monadology of Leibniz (its their reliance on the notion of substance and causes that allies them with Aristotle).
Still one musn't simplify a complex debate too far, for example Russell said in his Short History that a naive realism led to insuperable difficulties and in the preface to Wittgensteins Tractatus he also questioned how far the logical analysis of language into propositions together with the Correspondance theory of truth (and in one sense completing the Viennese programme) solved the higher questions; an assessment it seemed that was shared by Wittgenstein judging by the final section of the Tractatus.
Still those were early days for Analytic philosophy.