Domain names cannot be transferred from one registrar to another if there is an outstanding invoice due for the domain. Once the expiration date passes for domain renewal, there is an outstanding invoice in effect from the current registrar (until at least a one-year renewal is paid), which prevents the domain from being able to be transferred.
If you want to keep the domain, you should renew it with the current registrar then wait 45 days to transfer the domain to the new registrar. This way you will not lose the time you paid for and you always gain a year of registration when you transfer a domain name from registrar to registrar.
If you need your domain to work with your hosting prior to the transfer, you can always point your domain to our name servers or do IP Pointing. Contact us for any clarifications here.