This is a Notable Operational milestone.
The designation of the aircraft appears differently in various references. SP-GIL was the civil registration given to the aircraft. In an AHS paper, GIL BŻ-1 refers to some form of Type designation based on the letters of National Aviation Intitute (Główny Instytut Lotnictwa or GIL) and the initials of the primary designer Bronisław Żurakowski (BŻ). In the source reference below, GIL is the name 'Bullfinch'.
Note: Only the month and year of this milestone are accurate
Source: "Helicopter: SP-GIL", Polish Aviation Museum | Collection web site, 26 Feb 2017 (last retrieved date)