The Acharonim disagree over what is preferable: praying vatikin individually, or praying in a minyan after the time of vatikin? Some say that since the Chachamim praise the person who prays vatikin and teach that no harm befalls him the whole day, it is better to pray vatikin individually. Still, others say that it is preferable to pray in a minyan, for prayer in a minyan is sure to be heard. Additionally, there are doubts regarding the precise time of vatikin (as clarified in halachah 6), and it is not proper that an uncertain vatikin prayer takes precedence over prayer in a minyan. Therefore, it is customary to teach that prayer in a minyan is preferable. However a person who regularly prays vatikin in a minyan, and one day does not have a minyan for vatikin, is permitted to pray vatikin individually on that day, so as not to stray from his custom.
Regarding a person who has two options, to pray in a minyan before netz, which is the time of prayer b’dieved, or to pray individually afterwards at vatikin, there is disagreement. According to many, it is preferable that he pray individually at vatikin. Still, there are those who say that it is better to pray in a minyan before netz, provided that he starts reciting Birkot Keriat Shema after misheyakir. It is advisable for one to ask his rabbi concerning this. If the regular minyan before netz will be canceled because a number of people decide to pray at vatikin individually, it is preferable that everyone prays together in a minyan before netz.
.According to the Mahari Schwartz, it is preferable to pray vatikin, and according to Rabbi Shlomo Kluger in HaElef Lecha Shlomo 47, it is preferable to pray in a minyan. See Yabia Omer, Orach Chaim, part 1, 4:9, who hinges the law on kavanah. He maintains that if a person concentrates well, he should pray vatikin, but if he is unable to have kavanah, it is best that he prays in a minyan. Shut Pri Yitzchak 2 writes that since there are doubts as to when exactly vatikin is (as explained in halachah 6), it is preferable to pray in a minyan rather than to pray with uncertainty at vatikin. That is how we are accustomed to rule. However, since there are those who disagree, an individual who wants to pray vatikin from time to time may rely on their opinions.Bei’ur Halachah 58:1 writes that people who are careful to pray vatikin every day in a minyan are permitted to pray individually when they do not have a minyan. In Halichot Shlomo 5:17 the explanation given is that these people have a sort of vow, both regarding praying vatikin and praying in a minyan, and therefore they may choose how they wish to practice.
.We learned in halachah 4 and in note 4 that according to the majority of poskim, as well as the rulings of the Shulchan Aruch 89:1 and the Mishnah Berurah 4, the time before netz is valid for prayer only b’dieved. Additionally, we learned in the previous note that there are those who say that even when the prayer in a minyan is conducted after netz, it is nevertheless preferable to pray at vatikin. Therefore, the result is that according to the majority of poskim, it is best to pray at vatikin individually and not before netz in a minyan. So writes the Avnei Yashfeh 14:1 and Yalkut Yosef 89:14.However, we learned that according to the Rosh and Rabbeinu Yerucham the time for prayer l’chatchilah starts from misheyakir, and the Mishnah Berurah 89:1 writes that people who are awake on Shavuot night may pray in a minyan before netz. Additionally, Yaskil Avdi, part 5, Orach Chaim 10:4, and Or L’Tzion, part 2, 7:4 write that it is preferable to pray in a minyan before netz, for that is a case of extenuating circumstances, since he will not have another minyan after that. That is also the opinion of the Chazon Ish (brought by the Ishei Yisrael 13:6).
It seems to me that as a ruling to many it is preferable to preserve the prayer in a minyan, for prayer in a minyan is accepted and the power of communal worship is important in preserving the permanence of prayer. Only for a person who wishes out of piety to pray at vatikin, it may be preferable to pray at vatikin. However, ordinarily, it is best to pray in a minyan before netz.
All the more so in a small community, where a few of the congregants must leave early for work and they will not have another opportunity to organize a minyan after netz, this is considered to be a case of extenuating circumstances, and they must arrange the minyan to pray before netz. It is proper even for those individuals who can pray later on, to participate as well. (Although, if they want to wake up early, complete the early minyan, respond to their Kaddish and Kedushah, and then pray vatikin later individually, they are permitted to do so).