DD1 has just told me that her mil announced on Christmas Day that, seeing as she will reach 70 next year, this we be her last turn at hosting Christmas. My first reaction was one of surprise. I am 2 years younger, and, at present, am fairly fit, and, subconsciously, assume that our arrangement of me doing it on alternate years will continue for the foreseeable future. However, with DH getting easily stressed, due to illness, and realising that circumstances can change in an instant, I can see that any of us might need to 'make this announcement' sooner than we think. There are 7 adults, and 5 DGC always.
I can understand also, in principle, that due to the behaviour of some adult DC, it might be tempting to stop the hosting, but, generally, the joy of seeing our grandchildren usually takes precedence with us grandparents!