If someone wants to start evening shabbos meal before night and had not daven maariv yet, lechatchila should he stop during the meal at tzeis hakochavim to do maariv ?
No, once he starts he may finish the meal as long as he is reminded to pray maariv when he is done. But one must mekabel shabbos and start before sunset for this to work.
start the meal before shkiah ? 30 minutes before tzeis hakochavim (zman maariv) is not enough ?
and even less, let says 10 minutes before tzeis could he start the meal because if not, and if he does maariv, his family / childs 'd have to wait about 30 minutes more (the time to wait tzeis + daven maariv)
there is no special to tolerance for family shabbos evening meal?
Once sunset arrives it’s a safek whether Shabbos has started and therefore assur to start the meal.
I dont understand why it is asur to start the meal while there is a safek (bein hashemashos) if it is yet shabbos or not…what is the point ?
Even if its a safek whether Shabbos has started can’t you be mekabel shabbos right after shkia and start the meal?
Because as soon as sunset arrives, you may daven Maariv, therefore you cannot push off davening Maariv to eat a meal.
Just so I understand fully: once sunset arrives, you can daven maariv and then immediately start the meal? Is there a need to wait until tzeis to start the meal?
Correct, you do not need to wait to start the meal. Although the Rabbi is not a fan of davening maariv before tzeis because one needs to repeat Krias Shrma and many times they forget to.