It varies, but 8 days for me, my dates so far are below.
"orderHistory": [{
"orderStatus": "40",
"statusDate": "2016-09-24T01:13:16+0100"
}, {
"orderStatus": "39",
"statusDate": "2016-09-22T07:09:33+0100"
}, {
"orderStatus": "30",
"statusDate": "2016-09-14T01:15:00+0100"
}, {...