I know I'm not going, but thought it might be helpful to let you know that if you are getting into Birmingham Snow Hill, Birmingham Moor Street or Digbeth Coach Station, there is a
free shuttle bus that goes between stations if you don't know where you're going, and it stops at the front of Birmingham New Street too.
It's called Stationlink and is usually Orange buses though sometimes white. They are meant to depart every 8 minutes but it depends on the traffic. They're pretty good as are intended for people who have mobility problems, prams, heavy shopping, or don't know Birmingham that well. I used it every day while I was pregnant and commuting as New Street to Jewellery Quarter is a bit of a trek to walk, but if I got to Snow Hill, it was way less far.
Only thing is it only goes round one way, so if you're at Moor Street you are better off walking to New Street as you'd be on the bus for ages going round everywhere else otherwise! I can't find online anywhere any info for times between stops, but if you called Centro they would be able to help. (Unless I find my leaflet in which case I'll edit this post!)
Sorry for sticking my nose in, just thought it may be of use to someone

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