Sky Q and Netflix

[Windymeadows]

Please bear with me on this one -just a little confused!

I have had Sky Q since 2019 and recently noticed that I could obtain an offer on Netflix for two months for no cost then £5 per month thereafter. 
My son had a spare log in on his Netflix subscription so I added that on to the main box.

I thought this was limited to just my main box   ( I.e . He  son only has one spare) as the minis asked for log on details too.

I then subscribed to the  two month zero cost Sky offer.

So I have one  sign in ( my sons) on the main box then the Sky Q offer on the other two.

Have I made a  mistake here - I.e my sons spare could have covered both the main and minis or have I done this right?

Apologies for being a numpty but just confused!

Many thanks

[PandJ2020]

NetFlix accounts can be used on any compatible device regardless of where they are bought, i.e. direct from NetFlix or via Sky.

The type of account (basic,standard,premium) sets the number of concurrent streams to 1, 2 or 4 respectively.

Direct via Sky then the HD pack upgrades the NF add on to standard and UHD as well to premium.

So it's up to you where you purchase and where you log in.  However, the NF terms do note that accounts must be not be shared to others outside your household.