If you have an active pledge to a creator - it will be charged on the 1st of each month in the pacific time zone. Creators can see payment statuses here.
Patreon processes payments on the 1st of each month for pledges made the previous month. Around the 1st of each month a banner will appear on your account stating: "We have started charging patrons for the monthly payments cycle. Please consult our newly updated Help Center if you have any questions!". This simply means that we have began charging patrons for their pledges. If a creator is using our charge upfront beta, we process payments immediately when a patron pledges and then again on the 1st of the next month.
Pledges automatically renew on the 1st of every month. If you wish to cancel your pledge, you need to delete your pledge prior to the 1st of the next month to avoid another charge.
Related articles for patrons:
More articles about payment process here.
Related articles for creators:
More articles about receiving payments here.