2nd ext dependant urgent plz

I have a doubt regarding my wife's dependent tier 1 visa.
My wife's tier 1dependent visa and my visa (I m the main applicant)both expire on 13th oct 2015.if I go for my 2nd extension on 1st dec 2014,should my wife also apply with me ?or is her tier 1 dependent visa valid till oct 2015?once I get my 2nd ext can I apply for my wife's visa by post on oct 1st 2015 for 2nd ext ?
Plz advice

Go12 wrote:I have a doubt regarding my wife's dependent tier 1 visa.
My wife's tier 1dependent visa and my visa (I m the main applicant)both expire on 13th oct 2015.if I go for my 2nd extension on 1st dec 2014,should my wife also apply with me ?or is her tier 1 dependent visa valid till oct 2015?once I get my 2nd ext can I apply for my wife's visa by post on oct 1st 2015 for 2nd ext ?
Plz advice

Your wife, need not apply with you. She can apply any time later before 13th oct 2015.

Thanx a lot,can any gurus too could confirm it ,plz

@Go12, consider @ tier1-immigrant as guru
he is right, extension is not closed for dependents after 05apr15

I know it's not closed but I wanted to know is that if I get my 2nd extension,will my dependents visa get invalid and she should apply again with me for ext?

it won't get invalid. Majority of people go for dependent extension, after getting extension of main applicants

Oh ok thanks