Impact of new bank account

Bugalugs

Having spent the last four years being sensible and trying to correct the financial 'wrongs' of my twenties, I was accepted for a First Direct bank account this week. My initial reaction was 'super excited' (because of their good reputation I've applied a couple of times over the past few years but have been declined).
Then I remembered that on applications you're often asked how long you've been with your current bank. In approx three years we hope to be in a position to have a good deposit and apply for a mortgage. Will three years with a bank be seen as a negative attribute or is that long enough?