Bubble popped BUT from midnight they don't exist! Confused

[ImNotCrazyIWasTested]

I have just had a text from my youngest DD nursery saying she has to isolate as she has been in contact with a positive case (yes at nearly 11pm). In 1 hour class bubbles are ending!
I wouldn't normally question such a request BUT dinnertime Wednesday I had a phone call to collect her as she needed to isolate then 6am Thursday morning I had a message from nursery saying she no longer needed to isolate.

I guess I'm just venting my frustration at yet another day of struggling to wfh when I shouldn't be at home.

We were messaged on the weekend about the class bubble closing but it did not say you have to isolate and there was no text which there always has been in the past. DD has had covid so I’ve decided I’m not keeping her in but I’m testing everyday.