Prompt for a recording when picking up the phone when NOT answering a call?

Hey all -
I have a rotary phone, hooked up to a grandstream ht801, hooked up to a raspberry pi with raspbx/freepbx on it. I originally had bigger plans for this but I’ve been lazy and dont have time, so I am hoping to just do this: Someone picks up the phone, it immediately plays a recorded message, then theres a beep and they leave a message thats stored on the rpi. Whats the simplest way I can get that to happen?

For a bit of background, if it helps… I’m doing a diy wedding phone guestbook thing. No way I’m paying hundreds of dollars for that when I can do it myself for less! And my bigger plans that I mentioned, if I manage to get to that point, is having a python script make a call to the phone when it sees a human face, and then itd do the same thing as I want it to do in the question above (only difference being itd be actually answering a phone call).

Looks like the inbound route may just go to an Announcement that plays the recordings and then sends the call to a VM.
What’s confusing for me is that you mentioned that ‘someone picks up the phone’, in the case above nobody is picking up the call. The system is answering to play the recording and send it to a mailbox.

You have to configure the GS ATA to auto-dial a string of digits when the phone goes off hook. I’m pretty sure it’s possible but I don’t know the device so I don’t know how. Once that’s done, you create a Misc Application with the same digit string and send them to whatever system destination you want, in this case sounds like voicemail.