Commute times certainly play a part, now I work close to home I an only using 8 out of the 11 which is maximum at our CC, but up until this job I was using 10-11 depending on traffic.

On the rebate, you will still get it for the days you attend but if say you take 60 days away and the rebate has a maximum of 45 away then you would end up full fee/holiday fee for the extra 15 (wasn't sure if that was clear).

For childcare I would get your name down as soon as possible (unless you get guaranteed a place through work) as demand is pretty high in most areas, with lots of centre's having wait lists (same with family day care).