I had redcare via Age Concern for my mum before she went into a home with dementia - it was a few years ago and it was all that was available.
Nowadays, the panic alarms are, I believe, entirely self contained using a sim card and mobile connectivity and include location information - so they are not reliant on local power or internet connection. That locational information could be life saving - one time my mother got very confused, left her flat and was wandering around outside in freezing conditions. Luckily someone heard her calling out and took her home, but she could easily have died that night and was so confused that she didn’t think to use her dongle which was still around her neck, and it is doubtful it would have been in range of her base station anyway. A modern system can also include geofencing and even positional data (if someone falls down), takes it off, or battery runs low and automatically alert. Just like redcare, the modern systems are manned 24/7 just the same.