Sounds like they will give the one-month warning that the pledge manager will close in late June or July (i.e., the PM won't close until August). From Firelock Games, posted yesterday:
We have no solid date on that yet. We will be sure to give you at least one month warning before we do. Right now it’s looking like we will make the announcement in late June - July
If it closes in August, that's pretty tight to meet their deadlines of delivering in October 2021. I suspect this one will slip a little (particularly given the comment above about having models to show off "in March"...!). I'm in no rush, but am also waiting on more pictures and details before I finalize my pledge. I am still very excited for this one!