if your refused a visa, as you've already mentioned you have 28 days to appeal, if you are refused you should write to the ECO manager at the embassy asking for reconsideration, so your refusal could be overturned then, if not then it will go to appeal, and that could take upto 6 months
, probably better to deal with the reasons for the refusal and re-apply than go to appeal.(thou that might be costly to re-apply
)
yes if your baby is born b4 you leave, you would need to apply for another settlement visa and also another fee