You change the PCB Footprint for a part by changing the Footprint assigned to the Schematic Symbol in the schematic. However, if you _just_ change the Footprint then the BoM information will be wrong. For example: a 1k 1% metal film resistor in an 1206 package _is a different part_ from a 1k 1% metal film resistor in an 0805 package. This is because it will have a different: * power dissipation * manufacturer part number * supplier part number * description * they may also have different suppliers and manufacturers. So when you ask about changing the Footprint for a part from 1206 to 0805, what you are actually talking about is changing from one part to a different part. Therefore, if you want to keep the BoM up to date with your changes then you either have to: 1. remove the affected parts and replace them with new ones from the library. At present the easiest way to do this is to use Find Similar Objects to identify and then delete all affected parts, then place one replacement part in the schematic and then simply copy that one and paste it all the others. You should note the part prefixes first and then change all the replacements to the old prefixes or be prepared to reannotate the schematic and thendeal with the changes when updating the PCB. Or;  2. use Find Similar Objects to identify all affected parts and then manually update each of the fields for Footprint, (using the Footprint Manager), Supplier, Supplier Number, Manufacturer, Manufacturer Number, link and Description. In either case you will then have to do Update PCB... or Import Changes... to bring the PCB up to date with the changes in the schematic.

@andyfierman ``` Thank you ```