Would love some opinions on this topic

We used have singing lessons each week with a lovely lady but she didn't do exams and did not sight read. So we changed ( based on a recommendation ) to another lovely lady !
The trouble is the new lady lives around 40 minutes away and that is when there is not traffic, so later in the evening or at the weekend. O loves her teacher and did really well with her in her last exam but as we do not have a weekly slot and because we are both so busy we can hardly get lessons and when we do they are not at an ideal time - this is no ones fault just the way it is !
So I suppose my first question is - how important are regular lessons and depending on the answer to that, can anyone recommend a teacher that does exams and site reads in SE London ?
I would like to reiterate O loves her teacher, it is just the travel and to time tabling that is driving me mad
