Mind her own...business...

When I used to work, I also had every Friday off ... I loved having a longer weekend! No way would I have given it up, unless to help out in an emergency. Stick with what you're happy doing.

I would definitely not agree to doing an extra day's work a week because another member of staff has moved on. It is management's job to get a replacement, not yours and definitely not your colleague's job to 'manage' you into the vacant slot.
All I can say is that from past experience, if you step into the breach the 'temporary' solution is very likely to turn into a 'permanent' solution. You took on the hours which suited you and the Company in good faith if the situation has changed it is for the management to resolve it in ways which suit both them and staff. A change in your hours clearly doesn't suit you so stick to your guns or you may find yourself in an untenable position.

I think it is for your Manager to suggest it if she would like you to increase your hours. It isn't for your colleague to ask you to do it.

You used the word "suggested". Was she maybe just suggesting and thinking you might like the extra hours?

If you don't want to work Fridays, wait until your Manager asks you and then say you have other commitments.

I'd try and avoid discussing the matter with people in the meantime.

Good luck.

Spot on Trendynannie6

It’s not up to you to sort out not your problem, you work part time you enjoy your fridays to yourself, I would say sorry I’m afraid I have other commitments for the foreseeable future

I do believe they will be looking at replacing her but couldn’t agree more...it really isn’t my problem. Unfortunately my colleague seems to think she has some sort of seniority position being (nearly) full time. Bloody cheek!
Thanks for the support x

Just smile and say you have other commitments on Fridays.
Presumably you have a contract which says which days you work.
If they want to change your conditions of employment you are not obliged to agree.

Oh! I see now. It's extra hours to your normal working week.

Stick with your original arrangements if you can. At least talk about it again.
If your colleague doesn't have seniority (just feels to her that she does because she works full time), it's a bit of a cheek her asking you, IMO isn't it?)

You are absolutely not being unreasonable. From what you say you haven't been approached by managers even, just your colleague? How do you know they are planning on replacing the other person even?

I would say nothing. Carry on doing the hours you are contracted for and IF a senior manager asks if you would like extra hours just say no you are happy as you are.

As much as you might want to help colleagues, it really isn't your problem.

Whilst there’s no obligation I’m miffed that it’s my colleague suggesting I do the extra hours! The management are dreadful and our Team Manager always seems to be off sick, on a course, at head office....not where she should be!

I agree love0c others can be jealous ...you are so right there...

Difficult one! Do they mean every Friday or just one? If every Friday I would say sorry but you have other commitments. It saves any bad feeling, not that there should be any but I do so remember colleagues can be very jealous! You work part time, they don't! If they are short staffed it is up to the management to sort out anyway. it is not for you to sort out.

Well, it doesn't seem so from what you've said.

The point is can you realistically suggest others take over the Friday slot, without hurting anyone's feelings?
Or are you obliged to do as you have been asked?

I would say stick to your guns.If there is too much work for this lady to cope with then another person should be employed to help her.If you like having your Friday to yourself you won’t be happy and would possibly resent this lady.Good luck?