Hi
@poppet35, Firstly, the 2 year rule applies if you are dismissed and want to make an unfair dismissal complaint to an employment tribunal. You could only do that if you have 2 years employment. It is a way of stopping frivolous unfair dismissal complaints and clogging up the appeals system.
Secondly, you haven't been dismissed yet, only suspended pending investigations. Do you have a copy of your employer's disciplinary procedure? If not, get one asap, and read it thoroughly. Your trade union should support you through all of this, even if you've not been with them for long. Before any kind of disciplinary hearing, you should get full details in writing of what the charges are against you, and if you don't understand anything, then tell the trade union, and insist upon getting full clarification, so that you can properly answer the charges. The trade union rep (preferably a full time officer, not your local rep at work, because the full time officer will be far better able to handle something like this - gross misconduct is a very serious charge). At any hearing, you will (or should) be given full chance to tell the panel your point of view and how things have led up to this situation. From what you have said, your own line manager values your contribution, and you should ask them to attend the hearing as your witness. They will also be able to explain just how busy you have been, and how much work you have been asked to cover, even though the job is supposed to be only 30 hrs. You really need to know EXACTLY what they mean by "gross misconduct"
Whilst you have time on your hands, sit down and write down everything you can remember about the job, the extra workloads that you had to carry, any incidents that might have happened, induction and training that you were given for the job, anything at all since you started working there. Note also how many other people there are in your department, what were their workloads like, why didn't you get any help (e.g. you gave notice twice & your manager persuaded you to stay - what did they do to make things better for you, did they reduce your excessive workload? Make a big issue about the fact you told your manager, they persuaded you to stay, but they still did little to put things right !!) (At least, that's how it seems to me, just reading your post). Try to keep things in a logical sequence. Find your job description, contract of employment, any local rules of your department, and any other documents that you were given when you joined, you may need to refer to these when you are formulating your defence. Particularly be clear about your contracted hours of work, when those times start and finish, and what the arrangments are for overtime. Did you ever get paid for any of the overtime that you worked? Were you given time off in lieu for the extra hours? Most of all, don't aproach this alone - insist upon talking to the trade union rep; this may involve the local rep first, that's ok - but keep pushing to get a full time officer rep. The full time officer should ask for evidence of what you've done that amounts to gross misconduct, and why that action is gross misconduct (as opposed to misconduct, capability, or anything else). Compare what they say against what is written in the company disciplinary policy - they may be exaggerating the charges - the TU can advise about this. What I'm trying to say is don't waste the time you have, be prepared for when you are called into a disciplinary hearing - but DON'T GO INTO A HEARING ALONE - EVER ! If they tell you it's just a meeting, still refuse to go without the FT trade union rep with you. They should arrange the meeting at a time that is mutually agreeable with the rep.
I've just rattled this off the top of my head, so I hope it isn't too jumbled for you to follow. I've been retired from work for about 8 yrs now, so my knowledge about employment law is decidedly rusty - but the points I've set out aboove are ones that applied in my time, and let's face it, they are simple 'natural justice' principles.
Last point - Attack is the best form of defence. I don't care how "nice" your manager is, you have to stand up for yourself in this life - nobody else will do it for you - so come out fighting !!! Your manager knew all about your workloads and that you weren't coping, but still they did nothing to support you - or if they, did, it wasn't enough.
I notice that there have been other posts since I started this, so probably some of it will be repeats of what others have said. I'll post it anyway, because it will probably take longer to amend things. Have a think, and come back if you need further help.