PBS dependent visa extension outside of uk

Dear folks,

My wife's PBS dependent visa (Tier 2) will be expired at the end of 2019. For Visa extension, she needs to apply in the UK.

Is that possible to apply outside of the UK when her current visa expires? She may get a new enter clearance and BRP once re-enter the UK. If she is doing so, will the continued 5 years period for ILR re-count?

Many thanks

As you appear to hold ILR, it really would be more simpler if she applied within the UK for her extension. Applications from outside the UK are not 'extensions', they are new entry clearance.