On Thursday the big guy gets to invite all his best pals over for a fine supper. In that part of the world suppers start late and run long, so no hangin' yet.
Friday comes around. Since it's not Black Friday one cannot expect people to be lined up waiting to sneer at the freak carrying his own death up the hill, so let's say mid-morning, probably after lunch before he's all nailed up. Death by being nailed to wood takes a while; I would not expect it that day but perhaps they were some righteous big nails. Maybe dusk.
At this point they remove the corpse and burn the midnight oil entombing it. Me, I'd have set up bonfires on the hill so the people of your homegrown cult can watch the crows feast, and come the morning paid street kids to go up the hill and shout and spit, repeat until corpse is stinky, then toss it into a hole. Much better way to demoralize the cult. But they might not have read many books about conquerors, and my mind is a scary place. Whatever. Tomb, let's call it fairly late Friday.
Not much happens on Saturday. I mean, it does in that eggs need to be coloured and chocolate melted and poured into bunny-shaped molds, but aside from a few people weeping outside the tomb.. come on, for the Holy Week this day doesn't even get a name. Fast forward.
Sunday someone realizes the tomb needs cleaning so opens it. Pouf! No body. It must be early to mid-day so they could see. According to the timeline (which assumes a rapid death and a highly efficient cleanup crew) this suggests at most two chronological days, likely a bit short of that. Yet it is written in canon that he rose on the third day, because they used calendar days. If I went to bed at 11p and woke up two hours later one would hardly say that I slept for two days. I can just see the petty accountant waiting there late Friday outside the tomb, peering closely at a sundial, saying "yup, tomb closed at 11:56pm. you boys barely made the deadline.".
Anyway, happy nameless day, y'all. May your plaid eggs turn out pretty.