Bit of background. I rehomed a beautiful but almost feral silvery white goldie some years ago. She was about 2 /3yrs old when we got her (records not kept) from a neglectful home, and wasn't house trained or any sort of trained really.
It took lots of patience but she responded really well to positive reinforcement, lots of love and a regular routine and we went to training classes mainly for me to learn the best way to deal with her. She is very placid and generally well behaved. Recall is good close to me or middle distance but she has always been one for having a good yomp across the fields near us and as long as I could see her I didn't mind as long as I could attract her attention with the whistle. We developed a system of signals & whistles to keep her with us, she would go in big circles around us but always with us IYSWIM. She would always catch up towards the end of the walk and stay close till we got to the car or home. (our walks are always in safe areas no roads or livestock)
Fast forward to last year and she is now 10 and has over the last 6 months become a nightmare to walk off lead, running off like a greyhound at differing points, so I can't anticipate when to intervene, not responding to recall unless she is ready to and going miles on her own which I really don't like. She always comes back eventually but sometimes a good 20/30 mins after I have returned to the car. I have had the embarrassment of several good folks catching her & ringing me to say they've got her & one time she was 5 miles away
which worries me that one day it might not be a kind dog lover and she'll be stolen. I don't know if it's relevant but I broke my ankle last year so relied on a variety of folks to help walk her, but she was getting worse before then.
SO I have returned to long lead walking and training her with lots of praise and fuss when she returns to me. However every time I think she is improving and slowly move on to letting her go loose again to test her distance recall she is off. Its worrying me and TBH spoiling the enjoyment of my walks, I could just keep her on a lead but she loves and needs her long yomps and I love seeing her bounding across the fields but not if it's putting her at risk.
HELP oh wise doggy people of MN!