LLBL becomes thicker dramatically and at its inner boundary surge with large charge is created. Deeper penetration of LLBL into magnetosphere creates local increasing of cross-tail field in the tail and of FAC in the morning and evening sectors. Cross-tail current increases. Ionospheric conductivity increased due to injections and cross-tail current diverses into ionosphere. The substorm current wedge is established.
Surge passes the auroral band and moves downtail.
The field-aligned current shifts to higher latitudes . It looks like expansion. The main current moves poleward from this point. At this time other measuring points show the end of the expansion. Set up of background-state situation.