You will start at the next available number. For a series that is starting up in a month, that would be the first issue, but if that issue is two weeks away, then you would start at #2. I need to repeat this, because it can be confusing. We start you on the next available issue, not from the start of a series. If the next issue is #25, and you sign up three weeks before it is released, you would get #25. If you are looking for back issues, please contact us and we will see if we can get you a copy of the issues you need. In many cases, the previous issues will have been collected as trade paperbacks, or we may have some copies available for sale.