Reference Price Methodology for 2027-2029 Downloads Reference Price Methodology no. 4/KSP/SGT for the combined natural gas entry/exit system, operated by Operator Gazociągów Przesyłowych GAZ-SYSTEM S.A., for the period from 1 January 2027, 6.00 a.m. to 1 January 2030, 6.00 a.m. pdf, 720.43 KB, 27.04.2026 Publication date: 27.04.2026 Modification date: 04.05.2026