In the hour before a major release, price often drifts in one direction without apparent cause. A clean trend forms, a pullback gives an entry, and everything looks fine.
Part of this is positioning. Large participants adjust exposure ahead of the event. Part is lower liquidity, which allows small orders to move price farther than usual. Neither says anything about direction after the release.
The danger is treating the drift as a signal. When the number arrives, the move can reverse completely, and the apparent trend was just a prelude.
A useful test is checking past events. Mark the hour before each major release in a journal or on charts, note the direction of drift, and compare it to the reaction. The relationship is usually weak or inconsistent.
Even without that, a rule against opening new trades in the final thirty minutes before top-tier events removes a category of avoidable losses.
How does price behave in the hour before major news on the pairs you trade, and does the drift mean anything?