Removing broody from chicks - How do I do it and when?

I'm back again, this time for your font of knowledge on when to send my broody back to the other two adults.
My four chicks will be six weeks old on Tuesday and although pretty independent during the day, (especially the boys), still come running at mums call and tuck up under her every night and also for naps during the day. Mum is more than happy for this to happen and is still watching out for them during the day and not showing signs of ignoring them or trying to get away.
When mum returns to the other two adults, she will still be within sight and sound of the chicks and also has the added issue that both the other two (silly idiot) adults are broody I try to keep the broody adults locked downstairs and they've had a good look at Tak and the chicks over the last week. They seem pretty laid back with the chicks and Mum digging around in the wood chip just outside the main coop. The chicks and mum have had the run of the garden over the last few weeks, with the broodys locked in the main coop. I cannot move the chicks run any further away from the adults as all within an electric fence and have foxes very close.
When should I remove mum, should I do it at night (as you would when introducing new chickens) and is there going to be fireworks as I'm introducing lone chicken to a flock, or with chicks and mum desperately trying to get back to each other as they are within sight?

Cheers.

We used to separate mum from the chicks at 6 weeks, but if she is still fine with them you could leave it a bit longer. They will be going onto rearers pellets around now as well. You are right about the re-introduction of mum to the flock BB. You are introducing a single chicken and it will need handling with care- a mistake we made was putting one straight back in. In our case in her weakened state she got badly beaten and lost all her confidence permanently- she was the top hen before being separated. I must add though that in our case the broody and chicks were out of sight of the original flock and perhaps that was the main reason for the problem.

I would leave them be until Mum shows signs of being fed up with them - it will be quite clear when this is, she will probably pace the fence and possibly call to the others - as you don't need the extra hassle of the chicks missing Mum and vice versa. Then I would reintroduce with care as you would a new bird, so a nighttime introduction is a good idea. Sometimes it is not a problem and the Mum just slots straight back in, but equally the flock dynamics are naturally likely to have changed during her absence so sometimes there are problems. In your case, if the other 2 are still broody when Mum returns, then they will probably ignore her except if she tries to lay in their box.

Lovely picture BTW

Thanks both.
Tak was top hen till she moved to the little coop to be a mum. She has been within sight of the other 2 adults the whole time (obviously not when in the house brooding). shes not showing any signs of laying and has done a partial moult after the chicks where born, so don't think a few growers pellets will hurt if I start mixing them into the chicks food?
I have two added issues, I have two chicks on order from a breeder, both four days older than mine. I can't introduce to the other chicks until mum leaves and not sure how long the breeder will hold them for me.
I have also just managed to rehome one of the boys (the blue one), he's off to a lovely smallholding with 3 Pekin girls that I think are a bit older than him. the lady is coming to pick him up on Saturday. He started crowing at 6am this morning so although a little noise, glad she wanted him and it seems perfect timing. Hoping nobodies going to tell me it's far to early to seperate him