We had arranged to bubble with BIL’s household for Christmas. (2 households in total.)
We’ve now all been put in tier 3 and they messaged me to cancel. Their reasons were that we all have school age DC at different schools which is a risk.
AIBU to be upset by this? Dc are devastated, dd cried so much when we told her last night.
If they were shielding, I’d feel less upset but they go to the gym, the shops etc all the time, their DC have been going to their usual dance club etc. I did point this out that their dc mix with others at clubs but apparently that’s different as they take their temperature and the dance place has a covid safe certificate 
We had planned lots of ways to make it as Covid safe as possible too including wrapping up warm and sitting outside with a heater to open gifts, letting the dc play in the garden, keeping windows open all the time, sitting 2m apart.
I probably am BU but we’ve bought all the food too!
I’ve said that we’ll plan lots of special things to do at home for our family instead, have a bake off day with the dc one day, crafting etc
AIBU to be upset about their reasons for cancelling?