Tier2 ICT Technical amendment to CoS

[Gajalak]

My company applied for tier2 ICT visa for me and Visa sticker is on passport(certificate number of cos mentioned). While applying for visa, my company gave cos with say address1 in London as my work location(client place), but now asking to work for diff client but in London itself.say address 2 but in London.
My queries are:
1) is technical amendment needed in this case even though my role, CTC, city doesn't change too?? ?
2) if yes, then should I again go through vfs and passport submission and any fees additionally?
3)My travel is booked and is it possible in 7 days in hand to travel
4) my dependent's Visa is a day away and would come soon too with sticker, so should I re-submit dependent visa too?
5) charges again??

I'm worried please help...