The below chat script gives you full information about the time zone changes for Adwords and google analytics.
info: Thank you for contacting Google AdWords. Please hold a moment while we route your chat to a specialist who will help you with your question: "Time zone change".
info: Sabina has received your message and will be right with you.
Sabina: Hello Kamal. Thanks for contacting Google AdWords. I'm happy to help you.
KamalChandran: I would like to change the time zone of my analytics account. Is it possible?
Sabina: Let me check this for you.
Sabina: Please give me a few minutes.
Sabina: Thanks for waiting.
Sabina: You can change the time zone in Analytics in the "Main Website Profile
Sabina: Information" section of your "Profile Settings" page.
Sabina: If your Analytics account is linked to an AdWords account, the time
Sabina: zones will be synchronized and controlled by AdWords. Learn more about
Sabina: this at http://adwords.google.com/support/bin/answer.py?answer=32346.
KamalChandran: I have linked my adwords account with analytics account.
KamalChandran: the same adwords time zone will be applied to analytics time zone. Is that so?
Sabina: And we cannot change the time zone in the AdWords account.
KamalChandran: Is there any way to have a separate time zone for analytics account alone, even after linking both accounts; adwords and analytics?
Sabina: I am sorry we do not have that option.
KamalChandran: Will it be possible for you to change my adwords time zone?
Sabina: Kamal, I can change the time zone only once in your AdWords account.
KamalChandran: I would be placing a request with you for adwords time zone change in the near future. Hope you will assist me to change the time zone
Sabina: Yes, I can help you now.
KamalChandran: I understand the change can be done only once.
KamalChandran: I will get proper approval from my management for Adwords time zone change and will ask for you assitance.
Sabina: Sure, not a problem.
Sabina: If you chat in again, you can ask for me.
Sabina: Is there anything else that I can help you with?
KamalChandran: Sabina, the management wants to have two different time zone for both the accounts!!
KamalChandran: I mean adwords and analytics, Is there any other way, I am asking you once again...
Sabina: Kamal, if your Analytics account is linked to an AdWords account we cannot have different time zones.
KamalChandran: Is it possible to de-link the accounts and then change the time zones
Sabina: Yes, you can do that.
Sabina: However, if you link the accounts again then it will change according your AdWords account.
KamalChandran: what would be the drawback then..........
KamalChandran: I think the adwords data would not be reported correctly if I have two different time zones.......for eg:- conversion etc
KamalChandran: Am I right?
KamalChandran: what would you suggest, is it better to run both the accounts at the same time zone?
Sabina: If you link the accounts then the time zones will be the same.
KamalChandran: thank a lot for you support
Sabina: You're welcome.
Sabina: It was a pleasure chatting with you. If you have any more questions, please feel free to visit our Help Center. You can also print this chat transcript for your records. Have a great day.
KamalChandran: I will come back to you in a couple of days