The balancing regime uses Near Real Time (NRT) allocations to calculate the current Portfolio Imbalance Signal (POS). At the end of a gas month, the accountable offline allocations are published. Click this link for an (indicative) overview when offline allocations will be available on Gasport/B2B.
Any differences between the NRT and offline allocations are settled against the neutral gas price of the relevant day. For every day in a month, the net difference between the NRT and the offline allocations is invoiced via the settlement invoice.