Ring free day trial - not really free?

Hi! I was wondering if anyone can explain this to me please. I signed up to the 30 day free trial for my new doorbell. This trial ends on November 11th 2021. I have chosen to do the yearly plan thereafter, however, my next billing will be October 13th 2022 (different dates due to me not setting up the subscription straight away, Understand that bit). BUT that’s actually only 11 months, not a yearly subscription - I’m suppose to be having a 30 day free trial so surely my next bill should arrive in November, (a year after my free trial ends and my yearly subscription begins) not October. Is it a clever trick to make you think you’re getting a 30 day free trial but in fact they take it off you at the end of the yearly subscription? Or am I totally wrong? Thank you!