when i went to buy a so cal select annual pass and it happen on a block out day and they let me in for the day for both parks since i have bought a new select pass. i was surprised i had no idea that would happen. try asking that at the ticket booth. good luck to you
Block-Out days NEVER apply on your first visit, regardless of whether you bought the pass online or at the ticket booths. Block-Out days apply on your second day till the end of your pass life.
The only exceptions to this rule is if you are renewing your pass on a block-out day at the ticket booths, upgrading a annual pass to a higher level annual pass, or upgrading a ticket to an annual pass which is blocked-out. In any of these cases they will let you in on a block-out day.