Yes to both questions
I am not sure how to do this.
There is a BT Open Reach line box with a lower plate that can be unscrewed. If I can remove this, will I be able to bypass the filter?
Yes, sorry, I should have said.
The phone line plugs into a BT ADSL box which is fitted to the wall where the line comes in to the property.
The upper half of the unit connects to the BT wireless hub.
Does this mean that I can go no further with the Panasonic phone?