Hi Mommy! It's perfectly fine to worry about entering a new environment especially for your child.
My daughter has Singapore Math subject too and just like you I was not aware of how it goes compared to her traditional Math subject in her playschool. So before she enters Grade 1 last school year, we opt for a Tutorial specializing in Singapore Math. We studied her books and we based the lesson according to the book.
We did this for a month before the school has to start. And it was really effective since she did not have a hard time catching up with the curriculum of the new school.
You can try that to your daughter as well. Look for a nearby tutorial school that offers reading & Singapore Math and inform the tutor that you want your child to have an introduction about the new Mathematics Method.
While at home, you can also start practicing it as well. So you will know how to help her with her homeworks.
Also, ask the school if they will be having seminars for Singapore Math. We have that in our school and it's a yearly event. That way, you will know how can both of you manage this new method.
Good luck! :)
Magbasa pa