ILR for family

I would appreciate it if anyone could explain to me in simple terms whether my wife and a daughter will get an ILR at the same time as I will if on the day of application (in person) I have 4 years on work permit but they have only 2 years and 3 months on dependent visa?

I think ... yes! Of course make sure their details are entered as dependants on the form SET(O), and supply their passports as well as yours, and you should all end up with ILR.

Assuming that you all get ILR, what will be different is a year later when you might apply for naturalisation. Your wife will not be permitted to apply at the same time as you because she will be failing the "was the applicant in the UK exactly five years before IND receive the application" test. You can enter your daughter on the form AN(NEW) and get her registered as British at the same time as you are Naturalised.

As soon as you are British your wife will be able to apply because then she will be married to a British Citizen ... you .... and therefore the test will be "was the applicant in the UK exactly three years before IND receive the application" and at that time she will pass that test.

Thank you very much for your prompt and exhaustive reply.
Could you possibly elaborate on my particular situation? The fact is that my daughter will be 18 years old just in 5 days after I’ve got four-year residency in the UK.So probably I will need to squeeze through into those 5 days.
Do you think I can go for IRL straight after 3 years and 11 months or it’s too risky as we’ll have 1 year more on work permit and they might not give us ILR till 4 years?
On the other hand if I go to Croydon 5 days before my daughter is 18 and something goes wrong I will lose too much as she is going to university next year and the fee will depend on her status.
Is there any risk of not getting ILR in time in those two options or I am exaggerating?
Maybe it would be safer for me to rely on, say, workpermits.com?

I think the answer to your question is clear from the form SET(O). If you look at note 4 on page 5 of 20 you will see that it says :-

Please do not apply more than 28 days before completing the qualifying period. If you apply earlier than that, your application is likely to be refused.

For you the qualifying period is four years, so you can apply from 28 days "before completing the qualifying period".

So that should get your daughter ILR. But of course she will no longer be a minor when you apply for naturalisation, so you will not be able to enter her on your form. Once she has been physically in the UK for five years she will need to apply for her own naturalisation.

So all three of you, in due course, will need to take and pass the Citizenship Test, in order to permit an application for naturalisation.

Thank you so much for clarification, it's been very helpful.