It seems The Saturdays Tour Documentary is due to air on Saturday 14th May and Sunday 15th May on Channel4 (T4) of which at present its FIVE airings of 20mins ….
Currently it says:
10:00 – 10:20am and 12:00 – 12:20pm on Saturday 14th May and
7:30am – 7.50am, 10:20 – 11:40am and 11:40 – 12:00pm on Sunday 15th May
More as and when we find it …..
Source: My TV Guide