Hi Nicki Flute
Its been a while since I played picc seriously, but there was a time when I was a fairly serious flute & picc player.
When I started the to play picc, I was already a decent flautist, and only pracitised one or the other at first, though mainly picc. I used the piccolo practice book too, which is a really good tutor.
I found the only thing that restricted my practise was flatmates/neighbours!
When I felt comfortable playing picc, I then used to practise changing between the instruments, which again took a bit of getting use to.
Am playing flute a bit more these days (having been inspired by reading various threads!
), but happily for my neighbours I haven't played piccolo for a long time! Not sure my ears could take it as now more used to hearing mellow tones of bassoon or cello these days!
Hope this helps!