To deliberately inconvenience my colleagues?

I would go in early if it was to replace a woman who had to get home to young children but not otherwise. I think really you have to let this company fall on its face. Their management is very poor and you are rescuing them time and again. They are not learning anything at all that way.

@MistletoeMoments It's more a moral dilemma. I'm 99% sure there's no cover in place so my colleagues are going to be inconvenienced by having to stay late.
Not my responsibility, but there's nothing really stopping me from coming in early just in case.

It's not a moral dilemma at all.

Listen to yourself. You said it yourself. It's not your responsibility.

Except you believe it is your reponsibility really........... and that everything will fall apart if you don't provide cover .........

Your managers know this and won't bother doing their job. Why should they when you're picking up the slack and doing their job for them?

You've already done cover for a protracted period of time without complaint It was supposed to only be for a couple of weeks, but he ended up being off for 7 months!
I was exhausted by the end of it

Management know who they can take advantage of and who won't put up with the shit.

I'm questioning if I should be more empathetic towards my nightshift colleagues who will doubtless be very tired.

Shouldn't you actually be questionng whether management shoud be more empathetic towards staff?

Don't get me started on the staffing levels. We have been screaming at management for years about being too short-staffed. I'm far from the only one who is drained and exhausted from working extra hours.

If you've been screaming at management for years about being short-staffed why exactly haven't they remedied the situation? - I presume it's because staff just work extra hours, while ending up drained and exhausted.
So, in fact management don't have to do anything at all ..........

My managers made all the right noises about how it's not my job to cover, but no suggestion as to an alternative arrangement.

Your managers have said it's not your job to cover. So believe them.

It's actually not your business whether they've made alternative arrangements or not.
And if you keep trying to cover up for their failures and short-comings, then nothing is ever going to change

Yes, we're all responsible for our own cover.
Where on earth do you work that you're responsible for your own cover??

You're majorly over - stepping your work responsibilities and ignoring management failings and by doing this you're making it difficult for yourself and your colleagues.

Your management is taking advantage of the fact that you all feel 'morally obliged'.
However difficult it feels, you have to hold them to account or nothing will ever change.

Stop feeling like you have to single-handedly 'save' everyone

You are not a bad person.

I was once aware that managers expected me to do something (play music/lead a choir) at an event, but I hadn’t been actually asked. It had just been assumed. It was so awkward as the day approached …

How have you been made aware that the colleague will be away? Any way to decrease those informal channels so that you can avoid this feeling you’re having right now. I assume the Night Shift colleagues would have access to that same information so I don’t see why it’s your, not her responsibility to double check with managers. Although no one should need to assume it check, you should be informed or contacted.

Is it possible the night shift person has already agreed to stay the extra hour?

If you are all responsible for your own cover how do you know the colleague who is having a long weekend (Friday? Friday and Monday?) off hasn't arranged alternate cover?

You haven't been asked so you go in as normal and do your job.

Exactly this.

There is no point complaining that you need more staff when you’re all plugging the gaps at your expense. The company has zero motivation to change the situation, it’s working for them.

OP doesn’t need to offer a reason, her private life outside of contracted working hours is her business. It’s sufficient for her to say (if asked) ‘I have a prior commitment’ end of.
However it sounds like OP is dedicated to her job and is genuinely concerned about staff complacency and there being no one to step up during her colleagues’ absence.

@MistletoeMoments if you keep ‘saving’ them by appearing without being asked, you’re enabling them to carry on and not change their processes. Don’t do it.

Normal annual leave or extra unpaid days? I’ve never heard of this.

Yeah I think you're overthinking it. Not your problem. Just go at your normal time.
Do you think a man would be sat here worrying about this on an evening ?

I voted YABU because your presuming that you will be expected to cover for them you haven’t actually been asked to so just go in at your normal time and do your own work and if that means that someone from night staff has to stay extra hour that’s just tough shit it won’t kill them to work a paid for extra hour and I will make them realise that they need to get cover in for this colleague in the future.

@MistletoeMoments by sticking to your own responsibities how would you be inconveniencing anyone?
You weren't asked on this occasion.
Do you think you're saving your colleague's reputation for being sick? Or are you trying to be a hero?

If your bosses are saying it's not your responsibility, then just go in as normal.

It's not your job to worry about it and they don't pay you for it either. Just repeat that to yourself every time something like this comes up. It'll take a while , but it will finally sink in.

I’d probably go in half an hour early. Split the inconvenience with the night shift person.

Correct answer.

I’d consider it presumptuous for you to decide management must have failed to arrange adequate staff over and on that you need to step in and start work earlier.
This is not your problem and, who knows, an arrangement may have been made, anyway.

Ah FFS leave the guy's job alone. It's not for you to decide to cover, and have the audacity to complain about how tired you feel by doing so.
Another agenda on your part. You have not been asked to do it so stop it.

You all need to stop working extra hours then.

Why would they listen to you screaming when they can put their fingers in their ears and benefit from you all working for free instead?

There's a word for people who do this and it's also something you drink tea out of.

If nothing changes, nothing changes. I'm glad you have decided to go in at your scheduled time.

Your colleague on leave is inconveniencing the night shift, not you. So are management for not maintaining minimum staffing levels. There are no proper arrangements for cover during sick absence and annual leave.

I understand the night shift colleague is your friend. Even though you know this extra hour will inconvenience them, I still think you are doing the right thing for everyone on the long run. .

If you haven't been asked to cover, then they have made other arrangements.

Why should she speak to her boss ? It’s not her issue, it’s up to management to sort this out.
op just go in at your normal time. If they do expect that you will cover I would at least expect the courtesy of the them asking you and not assuming anything.

What if the colleague you think you're inconveniencing has already agreed to cover? And you turn up early. Will you both be doing extra work? By doing something not pre-arranged you risk becoming more of a problem.

Wow, has someone really ruffled your feathers?