MIL situation after she arrived early

I think 6 of one, half a dozen of another.
She shouldn’t have turned up early. That’s basic. You weren’t free until 2.30 which she knew. That’s on her and she should be reminded of that. your work over running - can’t be helped although if I’d taken annual leave I’d have been firm about leaving on time personally, because I think boundaries are important.
Your youngest could have stayed with his nan for longer, especially given she was early and you both were working. It would have been polite for him to make her a drink and hang around until one of you had finished and come down. It would have been nice to have stayed longer and done his work later but if he didn’t know what time she was leaving I can understand him not wanting to delay indefinitely. Your eldest presumably knew his Nan was visiting that afternoon and should have got out of bed. Even if he got in at 5am he would have had 6-7hours sleep by that point and he’s a student, he’s used to working in much less. I think staying in is room was rude. He should have stuck his head round the door and said “oh gosh you’re early Nan, let me shower and sort myself out and I’ll be down” and then spent some time with her. Walking the dogs depends on the dogs. If they’re going to mither because they’re walked at 4pm in the dot every day we’d take them out to save the agro but otherwise they could have waited. I think a lot could have been helped by communication - “mom are you staying for a while after dinner as we need to walk the dogs at some point, so just need to decide when is best?” - we always have conversations like that when people are visiting. But equally I don’t think leaving DH with his mom for 30mins is rude but I suppose added to the rest and I can see why she felt like an after thought squeezed in.
Mostly I’d get DH to point out that you’d both taken time off work to see her, but that she’d arrived 2 hours early and why was that? It threw everyone off their schedules and caused some confusion as everyone had expected her to arrive and then stay later to have more quality time together once the chores were done.

She lives about 20 miles away and we see her every other week, more often if we are off work. We are seeing her again at the weekend for a meal for our son before he goes back to uni so she is involved in family life.

She definitely knew she was very early. She said she was and my husband said she’d have to help herself to anything as we’re working before he rushed back to his meeting.

She is married. She does a few hobbies and has friends.

From her perspective, kids staying in their rooms may have been rude as she didnt know the reasons behind it. Do they get on with her? Does she have far to travel? Do you see her often? It can be frustrating especially when she might not see you as much as she likes, but you both work and kids are much older. My Ex-MIL would always make a big deal out of dropping in, I didnt mind especially as my own parents are stereotypical boomers, but it would become exhausting knowing if we didnt drop everything she would sulk about it for several weeks…But then I kind of understood her frustration especially as she had nobody else…Although for good reason she was generally a spiteful bitch…So, no I dont think from what you have said you were unreasonable, but her frustrations might also be reasonable…But equally not your problem to resolve.

I think 6 of one, half a dozen of another.
She shouldn’t have turned up early. That’s basic. You weren’t free until 2.30 which she knew. That’s on her and she should be reminded of that. your work over running - can’t be helped although if I’d taken annual leave I’d have been firm about leaving on time personally, because I think boundaries are important.
Your youngest could have stayed with his nan for longer, especially given she was early and you both were working. It would have been polite for him to make her a drink and hang around until one of you had finished and come down. It would have been nice to have stayed longer and done his work later but if he didn’t know what time she was leaving I can understand him not wanting to delay indefinitely. Your eldest presumably knew his Nan was visiting that afternoon and should have got out of bed. Even if he got in at 5am he would have had 6-7hours sleep by that point and he’s a student, he’s used to working in much less. I think staying in is room was rude. He should have stuck his head round the door and said “oh gosh you’re early Nan, let me shower and sort myself out and I’ll be down” and then spent some time with her. Walking the dogs depends on the dogs. If they’re going to mither because they’re walked at 4pm in the dot every day we’d take them out to save the agro but otherwise they could have waited. I think a lot could have been helped by communication - “mom are you staying for a while after dinner as we need to walk the dogs at some point, so just need to decide when is best?” - we always have conversations like that when people are visiting. But equally I don’t think leaving DH with his mom for 30mins is rude but I suppose added to the rest and I can see why she felt like an after thought squeezed in.
Mostly I’d get DH to point out that you’d both taken time off work to see her, but that she’d arrived 2 hours early and why was that? It threw everyone off their schedules and caused some confusion as everyone had expected her to arrive and then stay later to have more quality time together once the chores were done.

I’m just highlighting why MIL may think they made little effort. Because they didn’t.

It's not ageism. It's expecting an adult to know what time she's supposed to show up and sticking to that time instead of rudely showing up 2.5 hours early when she was told no one would be available. It's actually the opposite because it's expecting a grown woman to be more mature than teenagers.

Ageism. 👎

Eh?
I said it was ageist to drag age into the mix, with that disparaging tone.

Rubbish.

Some of the older generation don't get working from home, they think you can just stop and chat. They have no concept of zoom or teams meetings online that you have commitments to at all. Hence your MIL arriving early thinking she'll have more time to chat. It's a learning curve... Why not send her a link so she can try it out, she may get it then.

Our daughter is a solicitor with one of the Big Five London law firms, our son-law is a software engineer for a Bosch subsidiary and our son is a senior academic and researcher at a London university. I can assure you that the hours they put in working from home far exceed normal working hours. Plenty of people working from home are professional, utterly reliable and trustworthy.

Ageism. 👎

Why can’t she make her own tea for a couple of hours? She’s an adult, not a toddler. My son needed sleep after work and a night out. Why should making tea for a capable grandmother, who has turned up early, get priority over his sleep. Should he go and visit her on his schedule, after work at 2am and demand tea because it suits him to visit then? This was his sleep time, it doesn’t matter that it’s at a different time.

If this was his one chance to see her for a year, it would be different, but he sees her often and is seeing her at the weekend before leaving for uni.

Ahaaaaaaa. If you think people stick to the rules when they wfh you must have come down in the last rainshower.

Right. Wfh. I'd be a rich woman if i had a pound for every time I phoned somewhere and heard dogs barking, children crying , irrelevant conversations in the background, or being put in hold coz the person didnt know what they were talking about. So I'm not very impressed with people's commitment to wfh .....and I certainly dont think you couldnt take 5 minutes out to make someone a cup of tea.

Why would they start earlier? They organised a time that suited them and fitted around work so they could spend the afternoon with MIL. MIL decided to turn up early! This is on her.
I can’t believe how many people are siding with the MIL.

It also wouldn't have killed the MIL to show up at the agreed time instead of 2 hours early when she already knew no one would be ready. Being polite doesn't stop just because you're old.

That’s what I pointed out. Your experience. Everyone has different experiences.