Question:
A person who came to Mincha and after saying Hashem sefosai tiftoch and Baruch ata Hashem realized there wouldn’t be asara mispallelim, may he say lamdeini chukecha and daven in a later minyan (where there will be asara), or do we say that once he started SE he may not stop, even though it won’t be tefilla btzibbur?
Answer:
The posuk H-shem sefosai… is considered the beginning of Shemona Esrei ( that it why it isn’t considered a hefsek between Go’al Yisroel and SE). Therefore since you already said the Posuk it is as if you already started SE and you can not stop now. Whatever level of tefillah b’tzibbuir it is, you are considered in middle of SE.
Best wishes
Sources:
M:B 111-1.
