They delay Zuhr prayer – should he pray with them or pray by himself?
Question

In my village they offer Zuhr prayer half an hour before the time for ‘Asr prayer begins. What is better – to pray with the congregation or pray when the time for Zuhr begins?.
Praise be to Allah.Firstly: 
The most beloved of deeds to Allah is prayer offered on time, as is stated in a saheeh report from the Prophet (peace and blessings of Allah be upon him). 
The Messenger of Allah (peace and blessings of Allah be upon him) would hasten to offer the prayer as soon as the time for it began, and his companions (may Allah be pleased with them) did likewise, in obedience to the command of Allah (interpretation of the meaning): 
“So hasten towards all that is good” [al-Baqarah 2:48] 
“And march forth in the way (which leads to) forgiveness from your Lord, and for Paradise as wide as the heavens and the earth, prepared for Al-Muttaqoon (the pious)” [Aal ‘Imraan 3:133]
yusuf Ali: Be quick in the race for…
So you must advise the people of your village to offer the prayer at the beginning of its time, as was the teaching of the Prophet (peace and blessings of Allah be upon him). 
Delaying the prayer to this extent may lead to missing it. 
But if there is an excuse for this delay, such as work or intense heat, then there is nothing wrong with that. The Sunnah is to delay Zuhr prayer when it is very hot, and this is what is called al-ibraad (waiting until it cools off). For more information on the ruling on this, please see the answer to question no. 39818. 
Secondly: 
With regard to whether it is better to pray by oneself at the beginning of the time for the prayer, or to pray in congregation at the end of the time, there is a difference of scholarly opinion. 
Some of them are of the view that the virtue of praying earlier takes precedence over the virtue of praying in congregation.  
Some were of the view that delaying the prayer in order to attain the virtue of praying in congregation is better than offering prayer by oneself at the beginning of the time.  
Some were of the view that it is mustahabb to pray twice, so as to attain both virtues. 
Al-Hattaab said in Mawaahib al-Jaleel (1/404): Praying by oneself at the beginning of the time for prayer is better that praying in congregation at the end of the time. Then he quoted that from Imam Maalik (may Allah have mercy on him).  
Al-Nawawi said in al-Majmoo’ (2/3030: The view that we favour is that he should do what the Prophet (peace and blessings of Allah be upon him) enjoined and pray twice: once at the beginning of the time by himself, so as to attain the virtue of praying at the beginning of the time, and again at the end in congregation, so as to attain the virtue of praying in congregation. If he wants to limit it to praying only once – if he is certain that the congregation will pray at the end of the time – then delaying it is better, so as to attain the virtue of praying in congregation, and because it is a communal obligation (fard kifaayah) according to the correct view, and it is an individual obligation (fard ‘ayn) according to another view of our madhhab . This is the view of Ibn Khuzaymah among our companions, and it is the view of Ahmad ibn Hanbal and a number of others. By doing that he avoids an area of dispute. No one suggested that he is sinning by delaying it, and it may be understood that if the delay is too great, then it is better to pray it earlier, but if the delay is slight, then  it is better to wait. And Allah knows best. End quote. 
Al-Bahooti said in Kashshaaf al-Qinaa’ (1/457): Praying in congregation takes precedence over praying at the beginning of the time in all cases, because it is obligatory, whereas praying at the beginning of the time is Sunnah, and there is no conflict between what is obligatory and what is Sunnah. End quote. 
What seems to be the  case – and Allah knows best – is that praying with the congregation of Muslims takes precedence over praying by oneself, because of the well known virtues of praying in congregation, and so as to ensure that prayer in congregation is established, and because the correct scholarly view is that praying in congregation is obligatory. 
But if it is too hard for you to wait until that time, then there is nothing wrong with you praying by yourself at the beginning of the time, if you cannot find anyone to pray in congregation with. 
And Allah knows best.