I am returning to the UK from Japan starting my job within a month and a half. My salary will be well above the threshold limit. While I was in Japan, I worked for 2 years and lost my Job in March 2020 (and due to covid19 I was stuck). For the past two years, I earned around £40k, however I was unemployed from April (that is 6 month).
Since I got my UK job offer very recently, my wife will be applying to come to the UK with me. Here, as supporting document I am adding my payslip for the last two years working in Japan, and my new contract + some savings.
Here's my question, does she need to apply for the visa application before my contract starts?, since GOV.UK saying I have to be within three months of starting my position, does it mean I have to be abroad while applying? is there any time limit? We are worried by the time she applied I will be in the UK already.
This is worrisome because we would like to avoid the six-month wait further

Many thanks and I am looking forward to hearing from you
