changing a stopcock

[dotto]

Hi guys i need to change a stopcock in a flat on the sixth floor of a block of flat. We managed to identify the common stopcock feeding the other flats and my question is:
Once i have turned the common stopcock off and cut in the rising main above the old stop cock ( which i will leave there), will all the water in the rising main to the other flats above the flat i am working on flood the place? If yes, should i then open the kitchen tap of my flat and once no water is coming out anymore make the cut in the rising main above the level of my kitchen tap? Thank you for your time.

 

[adlplumbing]

turn off oprn up tap ower down from you and flush highest toilet
but be prepared to pay for plumber if something goes wrong

 

[dotto]

Toilet runs on cwsc that's why I thought opening kitchen tap would get rid of water in rising main feeding flats above mine.......am I wrong in assuming that?

 

[adlplumbing]

flush it anyway just incase