The pound v other? I had been transferring my USA dollars pension every month over here and building up a savings account, to just the point below which my combined savings and checking would have triggered the requirement to report them to the IRS. I stopped doing that a few months ago and am moving money from my UK savings to my UK checking account to cover bills as needed. My US Social Security still comes direct debit to my UK account, but it's funneled through the Bank of Ireland so I am not sure what's going to happen with my April SS check if Brexit goes ahead on the 29th.
I don't anticipate keeping more than a month or two's extra expenses in pounds here for a while, until I see which way the wind is going to blow once it stops blowing all ways at once. I do have a UK credit card with a nice limit on it, so I'd have that to fall back on if needed. I also have three USA credit cards, two of which don't charge any foreign transaction fees and give me an excellent conversion rate. So I'd also have those, and can pay them directly from my USA bank account where my pension is deposited every month. At one point I had started the process of opening up an Irish bank account so that I could move pounds into Euros, but I don't think either currency is going to be such after Brexit that my money would be markedly better there than in USD.
Don't we all wish we had a crystal ball? If it's a hard Brexit I do think the pound will sink, and stay down for quite some time. But I'm no expert, and I'm wrong about currency more often than I'm correct. But I'm still playing it safe by keeping most of my income in USD. For the now.