DS(4) sudden separation anxiety

[Whatshallichangemyusernameto]

I posted this in chat the other day but there was no reply. Hoping the parenting topic will be a bit more successful…

I’m not exactly sure what I want from this thread. Maybe solidarity, maybe advice, maybe just to get it off my chest.
DH and I have DS, who has just turned 4. For context, I work 3 days a week (I finished mat leave when he was 10mo and he’s been at nursery on those days ever since). He has two days with me, and two (Saturday and Sunday) with both me and DH. He’s always been ok with being away from us (my parents babysit and he stays at theirs overnight once every couple of months or so).
In the past couple of weeks, he’s started asking whether DH or I will be there when I tell him plans. Eg “We’ll go to the park then go the shops.”
”With Mummy and Daddy?”
On Thursday, DH and I were supposed to fly to elsewhere in the UK for a gig. We would have been away for about 24hrs. However, the plane was delayed by many hours and we were stuck in the airport. During our wait, my parents asked if I’d FaceTime and he was inconsolable. Literally screaming. He’d been like it for hours, apparently. We couldn’t leave him in that state and came home.
Next weekend, we’re supposed to be attending a friend’s wedding locally (no children allowed - fair). We’re obviously not both to be able to go now. We’ve tried planning a very fun day with his grandparents but he’s having none of it.
I’m so perplexed about why he’s suddenly developed this separation anxiety and what I can do to help him. This week he’s got his first school stay and play and a visit to his new childminder without me (lunch for an hour). I’m just stuck.

Is it because he's aware of all the changes coming? Leaving nursery, starting school, new childminder? It's a lot for a 4 year old to process.

They'll be talking about it at nursery and he'll be aware he's leaving friends too.

Thank you for replying. That makes sense, I suppose. He’s the only one from his nursery going to his new school and he knows that. I’m just wondering how long this phase will last. I hate to think of him unsettled.

My son went through a terrible stage of separation anxiety when he was 4 and started school. Just knowing that he is going to start school can start a lot of insecurities. We got through this stage by just keeping to a routine and not making a big thing about 'starting school'. We spent a lot of quality time with him and tried to keep anything remotely stressful to a minimum. The stage does pass but best to spend all the time you can with him until then.

Visual supports like you drawing a cartoon strip on what will happen when you go away, calendars showing what to expect etc will help

My DS is 4 and has always been quite a clingy child and we've never left him overnight before (more to do with not having the support around us to do this)

But this past couple of weeks the separation anxiety seems to have increased massively he's at nursery 5 days a week with no issues but the other week had 2 school sessions and new swimming class and I think it's all this building up.

We're just making sure we explain things to him and not get frustrated when he is getting upset but equally showing him some things he has to do- for example we can't pick him from school when he starts so trying to encourage him to do the new things and leave us.

I'm sure it'll all change again soon but I know how frustrating it can be!