How many days could a dependent visa holder stay out of UKâ€

I am a tier 1 visa holder and my wife got the dependent visa. We would apply settlement together in March 2012 after the two years "together time".

she now needs to get back to our country for a while. In order to still qualify to get settlement visa, maximaly how many days could she stay out of the UK?

I knew there is a 3 month limit for the tier 1 holder, but i cannot find any specification for dependents.

thanks

There isn't any limits for dependants. However, may need to show at least two years living with you in the UK and partnership/marriage is still subsisting.