They usually update at around 8-9PM [PST]. She shouldn't sell out "too" fast, considering Max Factory usually has a pretty decent amount of stock, but I'll definitely pre-order as soon as she goes up.
Her being as popular as she is definitely increases the chances of her selling out early-on, but as long as you pre-order tonight you should be fine. I'm not taking any chances though!
*gets F5 key ready*
To be honest...this might be the first time I order two of a figure. I love Tharja that much, and would like a "back-up" for the future in-case anything happens to my current one on display. Knowing Max Factory, she will
never get a re-release, and this one will definitely increase in value on the aftermarket [and quite quickly, I'm guessing]. If you want a replacement, pre-ordering one before release is definitely advisable.
Not at this time.
Kotobukiya sometimes does "surprise" pre-orders, with some going up without indication [even re-releases of some]. The fact that so many Kotobukiya figures sell out within hours [sometimes shorter], makes this a stressful experience. AmiAmi usually staggers Kotobukiya pre-orders, though, offering batches up for a few nights after initial pre-order until they finally sell out.
There's always the Kotobukiya USA site if you miss out on Japanese pre-orders, they
should have her. Although I still go for Japanese sites since I'm usually already ordering items and I like to have the shipments combined.