to wonder why DS2 had a fleecy jumper on when I picked him up from nursery today.....

[ceebeegeebies]

and then to make things worse, the deputy manager who let me in said 'oh he has been a bit warm today' whilst his hair was plastered to his head due to sweat

Have words with who dressed him/ dropped him off for nursery. They are responsible.

did he have the jumper on when you dropped him off?

but surely the nursery are able to remove/add clothes as weather conditions change through the day? It's not a case of "he was wearing this when he was dropped off therefore must wear it all day"

No, jumper was in his bag - no intention of him actually needing it.

How old is he?

2.9 - I am fairly certain he would not have asked for his jumper on (mainly because he wouldn't have even known it was in his bag)

Oh that is odd then.
Perhaps he complained of being cold? Perhaps he got his tshirt dirty so they changed him?
You'll have to ask his key worker tomorrow.

I have never known him to complain of being cold as he is generally a very warm child and does sweat a lot....and, he still had the t-shirt on that I sent him in this morning and there is a spare t-shirt in his bag aswell!