I personally think it is very cheeky to ask your nanny to leave while you are on ML
How would you like your boss at work to say, Im pregnant, cant afford you for 4/6mths so go away, find another job, but then we want you back as normal in 6mths time
i have had 2 friends in that position, and they did go and find temp jobs and then went back, but I wouldnt do that.
I have has 3 bosses on ML, and in all 3 jobs I have stayed while mb on ml, I have my lovely mb on ml at the moment - I get paid the same, but do slightly shorter hours.
If ANY of them had suggested what you are saying, I would had left for good - we work to pay bills/mortgages etc and cant afford to be out of work for 6mths, and trying to find a temp job that will fit in is very hard
If your nanny is that fab, then please try to find a way of keeping her on, even if maybe as a share with a friend
you also need to think of your ds, who is prob very attached to your nanny, how would he feel, if you got rid of her, had a new baby and then brought in a new nanny - so 3 chnages in his little life that would affect him
you say you would feel funny having someone there while you are not working - trust me, having another pair of hands about to give you time to catch upon your sleep is great, or to take all the children out and give you a break