just looking at potential deals for when I move into new place, BT offering Fibre 250 but only with a phoneline included therefore price is higher. Meanwhile the max I can get with broadband only is Fibre 2 (~73Mbps), is there any way I can get Fibre 250 Broadband without a phoneline?
Are you possibly confusing phone line and landline.
You will always need a "landline" as this is the means by which your broadband is delivered to your property whether by copper cable or fibre cable. The cost of this landline is included in the broadband package.
What you can do without is a "landline phone". This means that you do not have to have a telephone package with your broadband package. This means that you will not be able to make or receive phone calls.