This information is so hard to come by so I'm posting here in response. The first quest comes very early in the game. I rejected it, and it never came back even after my whole squad is on end game armor.

Started another game, and this time I accepted and finished the first mission. And then for the 2nd and 3rd quest, these comes ridiculously early as well and you probably won't beat it with your newbie squad with stick weapons, so skip them and do it later. The council SPAMS you with it and there's no penalty whatsoever for not completing it when it shows up.

In short, don't skip the first mission, the following ones can be skipped.

This information is so hard to come by so I'm posting here in response. The first quest comes very early in the game. I rejected the quest, and it never came back even after my whole squad is on end game armor.

Started another game, and this time I accepted and finished the first mission. And then for the 2nd and 3rd quest, these come ridiculously early as well and you probably won't beat it with your newbie squad with stick weapons, so skip them and do it later. The council SPAMS you with the quest, but there's no penalty whatsoever for not completing the quest when it shows up.

In short, don't skip the first mission, the following ones can be skipped.