Dh has announced his retirement date and I feel irritated by it

honestly most people would interpret this the exact opposite. His announcement has freed you, because of course he will be doing everything for the dc and lots around the home.

She doesn't need to imagine it:

I feel a bit irritated by this timing. I was a sahm to our DC until youngest started school. I got a job that allowed flexibility and I did all school admin. Concerts. Assemblies. Sports Days etc.

What a nonsensical attitude. Say cheerfully great I will be so happy not to do bus passes etc and will be really good for you to be hands on with the kids. What fucking relevance or logic is it for him to expect you to do it? You’re working. You did it when he was working. You’ve done it for multiple dc, it’s very much his turn.
you can always take him to counseling and say how you feel, since talking to him doesn’t seem to be your strong point. In your shoes him being the present parent would be a non negotiable to the point of he could leave if he felt too special to take his turn doing all the child organising.

but if you refuse to tell him how you feel then you can just sit there resenting him. Up to you.

Make sure he does the chores and home admin

Seems like the dates are coincidental OP as opposed to him deliberately choosing your perceived easier option.
Please don't let this ruin your marriage.
Your husband can pick up and share family and life admin. Please discuss this and don't allow your resentment to fester.

When you say you used your inheritance - do you mean your DH didn’t contribute or you both put 50/50? Now you work how do the finances work?

He'll do lots don't worry! Teens need many drops and pick ups too.
My husband has realised this as well.

If he goes for day ling bike rides she'll still be the one having to deal with emergency situations and lifts and drama and school issues - and cooking dinner and the housework - because he'll be conveniently hours away by bike. That doesn't sound like any kind of silver lining for the OP!

Yeah he is retiring from.work, not parenting.
You parented full time, then you worked and did all the kids life admin on top of working. You shouldn't have taken it all on but that's done now.
If he is not working he can take that load off you, just as you carried it all for him

How old is he mid 50's /early 60's ? He won't have time to laze around with teens in the house.
I had 7 and they were full on in the teen years. Really busy and there was no way I would have put up with their birth dad retiring and leaving it to me.
My h who took them on was brilliant and has only retired because of medical problems and the kids have all left home.

I was prepared to say YABU, until I read the circumstances. You're not a SAHM, you work AND do childcare and child admin. He just works. You know him better than us and you have realised he's carried on working up until now, as it means no childcare.

If he chose to have kids when he was already an old man, he should still be working to pay for them/and or looking after them.

The moment he suggests starting a weekend hobby, you drag those kids kicking and screaming to some kind of activity that takes place at the weekends. More than one activity if you can. Or make dad do a weekend activity with them. Give him the school HW app and make him stay on top of it.

Retiring from working outside the home , not from life .Now he will be the SAHP with all that goes with it . You need to set out expectations from the start . He will be de facto parent now . Does he really thinks you will be making dinner when you come home from work when he's been there all day . Of course there will be days he won't be around if he does play golf , etc. but that can be scheduled for . And he will also be taxi man . Delivery acceptance man . Washing man.... It'll be great for you . If you set it out soon.

Imagine being the parents of primary aged children whilst both working full time! Your description of your life for the past 11 years or so make it sound like it was horrendous, and yet it’s what many working parents dream of.
How old are both of you?

You need to have the conversation or the resentment will tear your relationship apart

you can’t retire from being a husband and father

So you spent your inheritance on being a sahm? You lost on wages and career progression and you funded it all via your savings?
I know you would have had childcare costs otherwise but they would have been shared, presumably.

I think you need to say "I'm really looking forward to passing on the baton, it's been a tough X years but now I can see the light at the and of that to do list tunnel I'll admit I'm ready for it." Just act like it's obvious he will take those tasks on and pull him up on it if he doesn't.

He benefitted from Ops labour as part of the family.

His turn now. If he doesn't already cook and clean he'd better learn, you are far too busy at your important job and trying to get promoted!

Let him do everything in the teenage years.

Do you want to still be the primary parent as well?

If not, have this conversation! There's no reason you need to lift a finger at home once he has retired. Make that pretty damn clear.

He's 10 fucking years younger than me! I'm drawing most of my pensions, he's living off savings (and my pensions)!

Did I miss how old he will be when he retires? If he's over 60 I think it's probably reasonable.

Does he have a good private pension? Those teenage and uni years are so expensive !