Can spouse remain a Tier 2 PBS dependent after I switch to ILR

Hi,
I am currently on a Tier 2 and my wife is on a Tier 2 Dependent BRP. I will switch to ILR shortly (have a priority service appointment in 2 weeks. )
Q1. Will my wife's PBS Dependent BRP still remain valid until expiry in Jan 2022 even after I switch to ILR in August?
Q2. The reason we don't want to extend her stay as a dependent based on my ILR is that she has completed 10 years in the UK and is already eligible for ILR via 10 year route. However, super-priority appointments are currently not available for this route and we don't want to make a Standard application and wait 6+ months. (We expect emergency travel). Once we get to the payment page we are unable to proceed further. Has anybody had success with getting super-priority appointments for 10 yr ILR in recent months, or does anyone know when these appointments will open again?
Thanks.

1. Yes provided you are applying for ilr based on tier 2 with 5 years residence

2. Super priority is available for long residence ilr. Why do think long residence ilr is not eligible for super priority??? Most slots are avualbkr at lfger midnight. If you don't get one, it is because the limited number of available slots has been taken.