Yosemite bear canisters in winter?

I have been winter backpacking twice in yosemite, once up to little yosemite valley and once to dewey point. Both of the times when getting a permit, a bear canister requirement was not mentioned by the park rangers (although I had one with me).

I’m curious what the official policy is vs. what the rangers tolerate.  Context here is planning a large group trip later this month out of badger pass.

Any input on this?