1. Yes. Saw it only yesterday, and I happen to be seeing it
running for the past 6 months without fail (on Mon-Fri only).
2. I'm not sure. I only know a trip departs Alexandra Hospital for
Hougang at 5.51pm.
Fare is $2.50 per way.
It is a normal 12m private bus (PBXXXXA) with a
white-background-blue-words plastic board at the front window,
towards the nearside of the bus, with the big numbers "571" and the
fare in small fonts.
Note that 573, which goes to AMK Ave 3 & 6, comes together with
it. So look out for 2 private buses coming.