Just added visual voicemail to my plan (iPhone) and am looking for feedback...

Prior to adding this feature, if someone dialed me and left a voicemail, I received instant notification that I had voicemail waiting. After adding this feature, it seems as if it takes around 5 to 10 seconds before receiving a notification that I have voicemail waiting.

I'm assuming this delay is due to the Bell system needing to transcribe the message in text as well as send the audio snippet to the device but am not sure.

Could someone who has an iPhone and used both standard VM prior to moving to VVM confirm my assumptions or is the delay due to something else? Thank you!