BES plans support bis accounts as well(assuming your bes administrator hasn't blocked/restricted it)
Enable OTA access and create a bis account with your new company bb.
Its about 15 minute delay at max although its somewhat smart and will check faster the more email you receive.
Push contacts IS not supported on BIS...Only for BES.
You may be out of luck, unfortunately the built in system works practically flawlessly for BES integration.
Q10! <- Love the 9000!! It's everything I wanted (minus enough ON BOARD memory)!!
<-9700 ---! more memory! small screen&keypad :( ->