What information should the employment contract contain?

If you are in the middle of a contract, then cutting your wages is almost certainly a violation of your employment law rights. While I am by no means an expert on this matter, I did have a similar issue years ago - mid-contract wage cuts - and I hired anemployment attorney to fight the case on my behalf. It turned out that my employer was basically looking to scare people into taking the wage cut.

They got into some pretty serious legal trouble for their transgression, and nothing happened to me in terms of wage cuts after that. If you are between contracts, your employer can re-negotiate your salary, but as far as I am aware, if you are in an agreed-upon contract, they cannot just decide to reduce your salary. If you want to settle matters, contest this action with support from a legal professional.

Can you cash out your personal time off when you quit being a personal support worker?

We can't answer that, it will be governed by your employment contract and the laws of the area you live in.
Ask the Human Resources department of your employer.

When exceeds it will fall to "Sick leave WITH OUT PAY" it must have Doctor Certificate from the hospital. Without doctor certification it might fall to "TERMINATION" because it's questionable for long absent in work.

If that is what your contract of employment says then it must be so but it would be rather unconventional.

It would be more usual for the Saturday rate to continue until midnight, typically 1.5 times the weekday rate and then at midnight Sunday rates would apply, typically 2.0 times the weekday rate.
If you are a temporary worker they can pay you almost whatever they want but if you are a permanent employee you should have an employment contract setting out the terms.

In the UK this product would fall under the COSHH (control of substances hazardous to health) regulations.

Employers are supposed to obtain a COSHH information sheet for every product they use, keep the sheets in a folder and make the folder available for inspection. In fact it is strongly suggested employers request employees read it every six months. In addition to the product information sheets the folder should also contain risk assessments written by the employer or a consultant about how the substances are used within the company, what they are used for, the dangers of using them and what they should not be used for and the recommended procedures for dealing with accidents resulting from the use or misuse.

Lots of suppliers will provide information sheets automatically but sometimes a sheet must be requested.

There are difficulties obtaining complying information sheets when a substance is intended for domestic rather than industrial use, sourced from a retailer rather than a trade supplier or where the product presents little or no danger to the user.

In such cases it is considered sufficient for the employer to carry out such research about the product as is possible and also carry out any testing that might be needed and write his own information sheet along the lines of the official sheets, including the usual risk assessment.

Unless specified in your employment contract that you have a medical condition that can only be cured by free tea, I'm afraid you have to provide it yourself on your free time, not company time.

You are free to resign if contract is due. Is there is a contract there are sometimes rules about resigning. Check on that.

I am pretty sure they do not want you to leave because you are an excellent employer. Take this to your advantage and get a good wage raise!!!

Ask for a raise and better working conditions, or a promotion.

God Bless You!!