I agree with what Renata says about scouting.
I've had a look at the sheet, and basically everything will be as before, except everything that requires a whip will come two turns later (turns ending with 4 instead of 2). That means the capitol will still be on track to all its (non-whipped) builds, but the second town will be delayed two turns.
I just had another idea though that I haven't had the chance to try out yet. The idea being that we build the first settler "by hand", to complete on turn 47 and settle on turn 48 (with some clever roading to make that possible, we don't need the gold roaded until later). Writing comes in on turn 47 too, and we whip the Library on turn 48, having it up on turn 49, 6 turns earlier than in the plan above (and 4 turns earlier than in the old sheet). That would give us whips on turns ending with 8 instead, hence speeding up the later whip builds, but at the cost of some "ordinary" hammers. The capitol also builds a worker for the second town, which can start Granary right away instead.
As I said I haven't checked this second idea in a sheet, it may be much more costly in the long run. I will try it, but it's too late here now, I need to go

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EDIT: Here's the sheet for the "simple" fixed version, i.e. the first I mentioned: