"weekend" potty time?

DD just turned two and has been showing signs for a couple of months that she's ready to potty train (tells us when she's going, asks to be changed right away, very curious about potty behavior etc). I hadn't intended to start this early, but it seems like she might be ready. I have a three day weekend coming up and thought it would be a good time to start. The problem is that her school does not have a bathroom in her classroom, so if they are going to follow-through, they will have to take her to another room to use the bathroom, which could be a serious logistical problem (usually there are two teachers in the room, but there are times, like lunch breaks, when it drops down to one). One of her teachers is definitely encouraging me to wait until she moves into the next room, but that won't be until August (which, incidentally, is when we'll have a newborn and I really don't want to move into full PT mode then).

So, can we just work with her evenings and weekends for a few months until we're SURE she's ready to "hold it" a couple minutes until they can get her to the potty next door, or do I just put all of it on hold until she moves up a room? Possibly almot a year from now, if I can't handle the stress of potty training and the newborn at the same time...(which is a definite possibility...sleep deprivation is not a pretty thing on me)

 TIA for any advice you may have!