Spouse visa extension when the main applicant has received ILR

[Spirit_of_the_seas]

I have recently been granted Indefinite Leave to Remain (ILR) after holding Skilled Worker (Tier 2) route for five years, and my wife is required to extend her visa before the end of next year , therefore, I would appreciate clarification on whether her application should be submitted using the Skilled Worker dependant extension route or rather as the dependant of an ILR holder, whether it is permissible to reuse the Certificate of Sponsorship (CoS) number from my most recent CoS (which is due to expire next year), and which reference should be entered in the UAN field (i.e., my ILR reference number or the reference number from my last Skilled Worker renewal). In addition, as my wife will need to renew her passport next year, I would be grateful for guidance on whether the passport renewal should be completed before submitting the visa extension application, and whether her updated passport details can be amended later via the online immigration status page? or whether the visa renewal should be submitted first. Finally, I would like to know how early I can apply for my wife’s Skilled Worker dependant extension, given that her current visa expires in November 2026 and her passport expires in January 2027. Thank you.