To ask if you can sign out of laws?

[BeaAndTiscuits]

I work for a big hospitality company and my job title is "bench manager", so I'm technically only supposed to be management to cover etc but I rarely do a team shift now.
Since being a manager, I don't get a break. It's well known that managers don't get breaks and often joked about. Manager shifts are usually 8-4 or 3-11ish, but if it's busy then can be longer. Managers are to be available at all times, they have to authorise certain things through the tills, so there is no guaranteed time of an uninterrupted break on your shift. I have to make sure team get their breaks but I'm not to take one? I've mentioned it before and they say to take one before the store opens if you're on an opening shift, but I find that I don't even have time for it. The other managers come in almost an hour early to get things done, but I can't because of childcare, and the shift starts at 8, they just chose to come in earlier. The evening shift, the store is open all the time so when could I take a break. I'm not allowed to give my authorisation card to any employee, it's classed as a sackable offence, so even if I was to go for a break, someone more than likely will need to come get me to authorise a discount or a void etc.
Also, next week I have been rota'd for a close and then an open. So this is finishing between 22:30-23:00 and starting again at 8am. I thought that there had to be an 11hour gap in between shifts but one of the other managers said that that law doesn't apply to hospitality? Is that true?
Also in a few weeks I have been put on 2 shifts that are 8am-11pm, I said I would do it during the week (quiet shifts so not as tiring) to help out as another manager is on holiday and I felt bad about not being able to pick up an extra day, but they've put the shift at the weekend which is the busiest. They replied with "you'll have full team on so HOPEFULLY you'll be able to take a break at some point". I just find it hard to believe that they can get away with it.

I would find a new job but it's hard as I'm a single parent and this job is flexible around my childcare, but I'm starting to think they're taking the piss and I guess I just wanted to know if it's true that hospitality can sign you out of laws or that they don't apply in this industry.

Rules on rest breaks are explained here www.gov.uk/rest-breaks-work
You are entitled to 20mins proper rest when working 6+ hrs.

For what you are asking no, they can’t deny you your breaks. But are they? Can you not take 10 min her and another 10 mins there type thing? You can sign your right to the 48 hour rule ‘away’ but you always retain the right to opt back in.
afaik 9hours is the minimum time off between shifts.
hospitality is notoriously crap, long hours to work in, so I’m not surprised you are facing this - and the industry wonder why employee are hard to find.
You might get more definitive answers if you post in employment.

Whilst YOU can opt out of the 48 hour week, your employer cannot opt out of complying by the WTR (Working Time Regulations 1998). Check that out as yes, you should be having 11 hours rest between working days.