There are so many requirements now that you need more leaders.
Safeguarding support is needed for all holidays.
You have online security, prevent, GDPR, cybersecurity, extended careers support, and pastoral support, which were not needed when I was at school.
We have staff checking on missing children, doing home visits, hours of paperwork, CYPIC, and social worker involvement. Domestic violence, deaths, children in hospitals, filtering and monitoring, and more issues with Social media outside school than in, Drugs and vaping, child abuse and child-on-child
Agressive parents, drung parents, threats to staff and threats to school where we have to close. Dealing with issues outside school like county lines and drugs that impact on siblings. That is without parental complaints, theft, children without food, providing and washing uniforms, neglect under the SS thresholds and children of parents with issues, MH, drugs and alcohol. That is, without the occasional break-in at 2am or bike shed set on fire. Had someone on the roof in the middle of the night that SLT had to attend. Train as fire Marshalls, First aiders, give medicines, be asbestos trained (God knows why) and do anything else that comes your way.
Last Friday SS came to collect a child at 9.30pm and someone had to stay with them. Meetings usually start at 7.30 am, then throw in the unknowns, you may go the whole day without eating or a break, especially when you have parents crying in your office needing support. That is without staff sickness and budget restrictions. You still have to train, teach, mark, write reports, report CPoms or other system and most of the extra work is paid at a TLR 3 rate, which can often be just an additional £700 for the year to about £3300 for more responsibilities.
Schools are filling a massive SS hole in addition to their usual workload.