Smeagels Fella and Mrs Reddo are both right - very little home standby. I think I've had one day in the last 5 years.
However,......
What you have to watch is Line Training. During training you WILL do home standby, and there is a fair chance of doing something, albeit not necessarily at minimum notice. Once you're on-line, home standbys are largely a thing of the past. What you will do is standby ON TOUR, IN THE HOTEL (or at beach, pool etc!!)
Hope that helps.
spaniel