Could we clarify: some of the BAT moved, and some of it didn’t; and you want it all there to verify the Uphold… is this right?
EDIT:
I’m not sure why all the BAT didn’t transfer to your browser wallet. There is a known issue right now with BAT porting to Uphold. Support is working on a fix, and you should follow the thread for any status updates on this, in case you are/ will be affected by it.
For this left-behind BAT, you can try force-stopping the browser app, clear the cache (not the data), then restart the browser and see if it shifts the BAT,