Does a 2.5 yr old need nursery when I already have a nanny?

[superzero]

Not sure where to post but would like some opinions..
Long and boring, sorry!
I'm going back to work soon and my middle child is 2.5.Whilst on maternity leave he has continued to go to nursery 2 days per week where he is happy and settled.He had mild speech delay and was a less confident child than my eldest and this is partly why I kept him at nursery even though I wasn't working and he has come on amazingly, now speaking, singing and socializing well.
I've arranged to have a nanny to cover my 3 work days when I go back in January as it was the best solution for school pick-ups and fail-safe cover for 3 DCs.
My middle child will be able to go to pre-school at his brother's school next September and I was going to discontinue with nursery until then.
I'm now having second thoughts though especially as nursery will be free after his birthday in March due to the 15 hours thing.
I was thinking of keeping him in nursery for 1/2 , or 1 day per week until September.
This will make the childcare even more expensive but only until March.
But is it actually necessary?
If he went to nursery on one of the days that I am off, I would spend even less time with him.Is it better to be at home( or , more likely, at a toddler group) with mum and baby brother, or at a nursery with children his own age?Or I could put him in nursery for one of the nanny days and ask her to do a pick-up or drop off, but is this just a waste of money when I'm already paying for her to do childcare?
And do you think he would miss out if he suddenly has to spend 3 days with nanny and baby brother and doesn't go to nursery/pre-school for a whole 9 months?
Or am I overthinking the whole thing?
If you are still reading, thank you and what do you think?

I would keep him in nursery 1/2 a day until its free from April, on one of the nanny's days. You can easily fill her morning with childcare related chores (which make your life easier too).
I suppose it depends on how much spare cash you have.

I think if he likes nursery and is happy there then keep him in, on one of the nanny days. Or, a half day in one of "your" days and then you can have a morning with just the baby (luxury!) and the afternoon with both.

Ps I also found nursery was excellent for my DS - really helpful and developmental for him; much new than "just" childcare.

I have worked for families where they have done different things. One child did not start nursery until she was nearly 4, so was doing a couple of mornings/afternoon sessions in the year before going to school. Another family started their son in nursery a couple of mornings a week at age 2, then as got older did more sessions.

I think at age 4 a mixture is good. At age 2 and 3 I feel it may be helpful to some children, though others will be fine spending all day with nanny.

I would suggest you look at how few sessions you can do, such as would nursery let you do 2 mornings a week? Then could one of those fall on a day nanny works and one day fall on a day nanny does not work. That way it is only a short period of time which gives the peer group socialisation and independence time. It gives a little time for nanny to get on with other tasks, spend more 1:1 time with other child.

Look at funding, how many sessions minimum, are they morning, afternoon, mixture? Is the current nursery the best place or would somewhere else be more suitable, such as a pre-school from which many children go on to attend the local primary school?

Thanks for replies so far.Just writing this has helped think it through.
I agree nursery on a nanny day is probably what I should do.
cindy34 current nursery is the right place in that he knows the staff and has a few friends there.None of them will go to his school though as nursery was nearer my work than home.I don't want to change to a nursery nearer my home & school as it would only be for 9 months and might just be more unsettling.He is quite a babyish 2 year old .
They implied that even 1/2 a day a week was ok as they know him.
Pre-school at the local school only runs for the school year so can't go until September.
I might end up using a local nursery for the baby though.I was counting on him having 2 older brothers for learning about sharing and socialisation but this has made me think that maybe ,perhaps when he is around 2,he should have some nursery time too because as starkadder says,it is more than just childcare.

I think you should take him out - that be can benefit most from one on one time with your nanny.. He's too young

I think it depends on what the nanny will be doing with him. if she's able to take him regular playgroups, one o clock clubs etc then he may well get as much social benefit from those as he would from nursery (and it'll be a lot cheaper!) However if she won't be able to do that due to younger DC then I think one half day would be beneficial. Also good for the baby to have some one on one time.