It's completely possible for a tulpa to be formed in a day.  Matter of fact, I believe the reason older members end up taking longer for their tulpae to form is because of certain that the current guides have.  Some members and I decided to find out if this was true, and we had the perfect opportunity for two reasons.

First, the 3-day wait on accounts (when you register, you have to wait three days) was made, so less people were posting on the forums.  This this prevents frontloading on the forums from members, so when someone like this comes in saying that their tulpa is actually moving around, they won't be told it's too early or that they're not sentient yet.  Because guess what?  That's frontloading, and you can check out Purlox's latest article, you can read about creation times, etc.  I should note that there are tulpae who have sentient memories dating back to when the person said "I'm going to create a tulpa!" and tulpae that remember the creation stage, etc.

The second reason is that they're going to #tulpa.info (instead of #tulpa), which allows us to give our guidance directly to a new user when they come in (I should note, the 3-day wait also sends most new users to #tulpa.info anyway, now).

So, for the past several days, when a new member would come in, the first thing Purlox, I, and some other tulpae & creators would do, would remove all types of frontloading, give the dangers of even having hourcounts, and encouraging them to treat their tulpa as sentient from the very start.  Purlox has been taking aspects from several creators who had tulpae vocal quickly, and he's compiling them to a method for fast and optimized tulpa creation.

This is why the newer users are creating tulpae quicker, because they're applying new and optimized methods, plus they don't have the same fontloading that you, I, or other older members have had when we first started this.  They go into the process completely believing that a tulpa is sentient and vocal from the start, they ignore hour counts, and guess what happens, and happens quickly?

We're getting very good results with these new methods, and you can be assured in the coming weeks they'll be pushed to the main guides, or at the very least, the frontloading from Dane's will be taken down.

Update: So, I know of at least three people in IRC that weren't exposed to frontloading, and they now have sentient and vocal tulpae, instead of having to go 70+ hours before that sort of progress.  This helps further assert the frontloading in the current guides are toxic.

Also, what I noted in IRC:

23:07 <~Pleeb> Bascially, normally if what happened with Serena would have happened, Fuliam would have been assured that he was parroting, or accused roleplaying, because "It's impossible for tulpae to be active that quickly, you need at least 20 hours of personality before you can even start visualization, or your tupla  will be a servitor!"
23:07 <~Pleeb> And, "You need to spend at least X hours on this, and X hours on that, and tulpae WILL do this, and tulpae MUST do that, "etc...
23:08 <~Pleeb> And, "Your tulpa will not become vocal until about 70 hours in."
23:08 <~Pleeb> All this stuff, reading it, and being told this by the community,
23:08 <~Pleeb> it's toxic.
23:09 <~Pleeb> It's why I said "screw it" and started working to direct everyone here, to the IRC, where they can stay away from the frontloading before they even start.
23:10 <~Pleeb> So now, you have people that end up having tulpae in a matter of days -- something Chess and I are still fighting for.
23:15 This means that my judgement that the frontloading in the current guides are toxic, was correct.

Also, read Chupi's warning: http://chupitulpa.tumblr.com/post/29003607860