In actual CoS form you can't change the start date and end date. But there is a work around, there is an option in CoS form to provide Notes/Comments in that you can mention the new start date and end date. I did the same when I did the change of employer application this month. This need to be done...

And update,

Got the visa without any issues. I went to belfast PEO in person.

Thank you!

Thank you rex90,

Have you applied through post ? and when are you expecting your visa?

Hi, First of all thank you all for sharing valuable information on this forum. I am tier 2 general holder, now i am filing "Change of employer" application. My new employer had completed RLMT test according to the guide line, but I have one doubt they have not mentioned the range of salary...