We have about 30k recipients in our lists and every time we send a mailing (New Mailing - Submit Mailing - Schedule Jobs - Execute Process Mailing) it stops after 1000 messages. We usually have to refresh the page and continue until it completes. How can we work around this? Thanks for your kind help.
Did you setup the cronjob?
It's the usual behavior of civicrm to send 1000 mails per cronjob. After that it waits x Minutes and sends the next batch of mails at the next cron run.
Check "Mailer Batch Limit" at CiviMail Settings /civicrm/admin/mail?reset=1.
There must be zero if you want to be sent all mails at once.