My wife is getting a job which doesn't sponsor but pays more than current and offer better perks

So i want to know whether she can switch the visa from Tier 2 General Visa to Tier 2 Dependent visa in UK.
What about her Indefinite leave to remain clock?
Someone having ILR (Indefinite leave to remain) for her partner what would be requirement to get ILR?
Even though she had already lived in UK for 1 year masters, and 2 years on her own Tier 2 General Visa and 2 years on Tier 2 Dependent Visa.