Excellent work Jim. It’s important to remember that the PBs are just a bonus. If they come, great. If they don’t, it’s not a failure. What’s more important is you enjoy your running week to week. Enjoy the people you spend your time with. Enjoy the places it takes us. The best places in town, the park, the seafront. That’s the beauty of running, not the PBs. So don’t worry too much about that and never try to force it. If you stick with the training then the chances are the times will continue to improve. But it’s definitely not the most important thing.