To evaluate if your guitar’s pickup is the newest upgradeable version, you’ll need to get a mirror and a phone or flashlight to look into the sound hole. Position the mirror so that with the use of a flashlight or phone, you can clearly see the pickup connector on the inside of the guitar. You can even try to just use a cell phone by using the movie function with the light – if the focus is good enough, this will work as well.
The newer upgradeable pickups will have a socket with a 2mm connector that you can remove from the back of the pickup jack. This connector can be removed and re-routed to the active pickup module for upgrade. The picture below shows these as type A (which have no sleeve), and type B (which have a sleeve); both of these can be unplugged and upgraded.
The older non-upgradeable connectors (depicted below as type C) have heat-shrink tube where the connector jack and the 3 wires going to the under-saddle piezos connect. This pickup can’t be upgraded because the wires are soldered directly to the pickup connector