Skilled worker dependent extension

[Mars17]

I got my ILR, but my wife still didn’t complete 5 years.
So I’m applying an extension for her skilled workers dependent. Her Visa is expiring 23 May 2023.
I’ve 2 questions:
1- When paying the IHS; I was asked for the work expiry date, so I put the date for my ILR biometric which is 31/12/2024. So I paid for 2 years of IHS. Is this wrong ? should I have put 3 years from the date of my visa expiring? As I read here in the forum it has to be 3 years.

2- i now paid the IHS and the visa fees.
I see a message that I’ve up until 9 May to upload the documents.
I’ve to travel by end of May with my wife, does this mean this they will take 8 weeks to reply and hence travelling by end of May is not possible ?
I was expecting to see something to set for a biometric date.
Please advise. I’m so scared I screwed this up