The sequence goes:
SOTU end of January
Wilson makes some media appearances in February and March, before the war, on tv and a column in The Nation against the war but saying nothing about the uranium/Africa claim. And he does cite the SOTU, so we know he was aware of it.
In May we know he talks to Nicholas Kristoff about his story and in June the WaPo goes with a piece and then he outs himself in July.
At the same time in May in England the "sexed up dossier" charge is being made against Tony Blair. The charge, you might recall: Blair lied about intelligence. Sound familiar?