Complex sentence: The number of F-15J upgrades was increased from 26 to 48, and the MoD purchased the part of the modernization for 38 fighters, however, the full budget for modernization is incomplete.
Split into simpler sentences: The number of F-15J upgrades was increased from 26 to 48, and the MoD purchased part of the modernization for 38 fighters. However, the full budget for modernization is incomplete.