SLM Policy Naming

Hi,
I'm trying to upload an SLM policy and am getting the following error:

elasticsearch.exceptions.RequestError: RequestError(400, 'action_request_validation_exception', 'Validation Failed: 1: invalid snapshot name [slm-policy-{now{yyyyMMddHHmm}}]: must be lowercase;')

How can I fix this while specifying the snapshot naming format we require? The naming format is currently specified as slm-policy-{now{yyyyMMddHHmm}}.

Thx
D

I've experimented with workarounds for this and nothing has worked. It seems that the the snapshot name doesn't allow us to specify uppercase datemath arguments. Is there something we're doing wrong?