The Flash S1E18, All-Star Team Up has Ray and Felicity from Arrow show up in Central City. However, there were some oddities in their relationship that don't jive with their current state over in Arrow. A few weeks ago, back in Arrow S3E18, Public Enemy, Ray
tells Felicity that he loves her. She does not reciprocate, which starts a plot that clearly foreshadows them splitting up.
Yet there's no hint of this in the Flash episode. So I would assume that the Flash episode ended up airing later in sequence than it should have, knocking it out of sync with Arrow. My question is where it belongs chronologically so that these plot developments are in order.
When does The Flash S1E18 occur in relation to Arrow's 3rd season episodes?