As used for electricity, the time one hour before the start of a settlement period (see settlement period) when physical notifications (see Physical notification (PN)) are finalised under the Grid Code. Until November 2017, gate closure was also the time after which contracts for the sale of electricity could no longer be notified to Elexon under the Balancing and Settlement Code (BSC). From November 2017, under BSC P342 alternative modification, the deadline for these notifications (Energy Contract Volume Notification (ECVN) and Metered Volume Reallocation Notification (MVRN)) is the start of the settlement period (known as the "submission deadline" in the BSC). For more information, see Practice notes, Balancing and Settlement Code: an introduction and Electricity industry: overview: How is electricity traded?.