When flying from Malaysia to Madeira, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.
These are just IATA (International Air Transport Association) codes. They are used in aviation to identify and differentiate airports. That’s why a Kuala Lumpur Intl Airport to Funchal Madeira Airport flight would often be abbreviated as a KUL to FNC flight. Kota Kinabalu Airport (BKI), Penang Intl Airport (PEN), Kuching Airport (KCH), Johor Bahru Sultan Ismail Intl Airport (JHB), Langkawi Airport (LGK) are other airports near this flight route and their unique identifiers/IATA codes.