Either we have become accustomed to this activity or it has gone as it happens rarely now.
Should I bury quarts on the line at the front and back of the cottage and try and divert it over the top. Should I move house or simply ignore it?
Not sure what you mean specifically by "it happens rarely now"- is this referring to the Victorian stuff or everything?
What you do may well depend upon your belief system. Moving house is drastic but (i) what if these aberrations move with you? (ii) what about the people to whom you sell & your responsibilities to them...if they are as sensitive to this as you?
Do you believe that the quartz will work? In which case why haven't you already done it? (!)
Are you comfortable with using intent- if so, and it sounds as if you may be...because of "it rarely happens now" (my surmise being that it rarely happens as you don't want it to happen)...move the line to where it can do least harm- over or around. You may well be able to "use" an alternative route for the water from the well to the dry spring. Try visualising this and see what you get.
Or use the services of a professional dowser on the BSD register.