Yes, it is disliked for him to do that, and it is recommended for him to hasten iftar when the sun sets, even with a sip of water; as narrated by Sahl ibn Saad al-Saidi, may Allah be pleased with him, the Prophet (peace be upon him) said: ((People will continue to be in good as long as they hasten iftar)), in Sahih Ibn Hibban 8: 273. And from Abu Huraira, may Allah be pleased with him, the Prophet (peace be upon him) said: ((Religion will continue to be apparent as long as people hasten iftar, for the Jews and Christians delay)), in Sahih Ibn Hibban 8: 273, Al-Mustadrak 1: 596, and Sunan Abu Dawood 2: 305. And from Abu Huraira, may Allah be pleased with him, the Prophet (peace be upon him) said: Allah, the Exalted, said: ((My most beloved servants to Me are those who hasten to break their fast)), in Jami' at-Tirmidhi 3: 83, Sunan al-Bayhaqi al-Kabir 4: 237, and Sahih Ibn Hibban 8: 276.