Keep your money in your British bank, I kept mine in my HSBC account and drew what I needed when I needed it, no exchange charges or commision when you do this via an ATM, if you use an ATM linked to your own bank you probably won’t even get an ATM fee.
And visa versa if you need to send money back to uk. Get 2 bank cards and post one to uk to someone trustworthy to withdraw money if bills in uk still need to be paid
When we transfer from the UK —Canada we use Currenies Direct no charge over set amount and good rate and to whatever bank we want in Calgary, done this a few times with them very good
I’ve sent cash back to uk with pay pal relatively easy. Exc rate not brilliant but ok for small amounts.