I doubt I'm giving you new information but there isn't a lot of activity in DDB.
A pytivo push is done by logging into to our tivo account. The request is made on tivo's servers. I don't think I've ever had to wait more then 5 minutes.
Couldn't you use mfs_ftp to transfer shows without getting tivo's servers involved. Take a look at movie loader. You may be able to use that as a starting point.