you’re welcome, I’m glad I could help.
btw, I just noticed you posted a photo above showing your existing door sensor and magnet. That’s pretty well identical to what the clearance looks like on my door where I re-used the old magnet. I have the identical sort of deep door frame. I think you should have no problem using the old magnet with the new Ring sensor.
When you’re mounting the new sensor, you can take a look at where the standard Ring magnet (ie actual magnet inside its plastic housing) lines up with the alignment mark on the sensor body, and just make sure you mount the sensor so that the old magnet is positioned accordingly. Actually if you open the contact sensor body and take a close look, you can see the magnetic reed switch - that’s the thing that needs to be in close proximity to the magnet.