i've worked on about a dozen fondant cakes so far in my fewly acquired past-time, but i always leave them to the night before...in part b/c that's the type of person i am (one night i had 2 cakes to do!! ugh). but also b/c i don't know what to do with cake once it's done. i bake my cakes and freeze them so that is no problem. but if i were to completely finish a fondant cake (with fondant & gumpaste accents), what do you do? freeze? refrigerate? store in a box? help! i don't enjoy the last-minute pressure.
Leave them on the counter until it's time to deliver.
put the cake in box, then store in refrigerate (1 or 2 days it was still OK). I did same that way with birthday cakes and wedding cakes .