On Civi 4.7.27 send first large mailing to 12733 emails through SparkPost, only some were delivered (about 900), and the job says it has not completed. Unfortunately, it is 16h later and the Send Schedule Mailings (Entity: job Action: process_mailing) keeps succeeding every 5 minutes.
The settings were default, so the job attempted to send all 13k emails at once, which I confirmed by finding one child job still in state of 'Running' in the civicrm_mailing_job table with 0 offset and all mailings included.
My suspicion is that the job timed out.
How can I invoke a job that will complete the sending? Can I determine from one of the tables which emails have been sent to, and can I restart from there?