Changing job, 12 weeks notice on my contract

[sysy01]

from reading other posts, it is recommended to resign after CoS is assigned and new visa application is approved.


Am I allowed to work in old company using visa from new employer for 12 weeks long?

thanks

[orthodoc]

from reading other posts, it is recommended to resign after CoS is assigned and new visa application is approved.


Am I allowed to work in old company using visa from new employer for 12 weeks long?

thanks

Its a common problem with most people planning to switch employers on tier 2. Experts kindly advice.