GTV dependents visa extension once main applicant on ILR

Hello,

I have a couple of questions regarding the global talent dependent (my wife) where I have received the ILR. I will apply for an extension of her visa for 3 years. But the extension will still not complete her 5 year period and will be just 4 months short. I have following questions:

1. Would she need to get another 3 year extension as a GTV dependent to complete here 5 year period?
2. How soon can she apply before the expiry date of her current BRP?

3. In the wife's visa extension application form there is a question 'Yes, I have their biometric residence permit (BRP) number'. Does she need to insert my ILR permit number or my expired GTV brp number?

Thanking you in anticipation.

Best Regards