Sounds like a great NY resolution, and St Cuthbert may well fit the bill, but it isn't a simple matter of computing the daily distance. At first glance, 62 miles in 5 days sounds easy, but you need to consider the tides on your actual dates as well as your overnight stays.
The grand finale of the whole walk is the crossing to Lindisfarne, and not only is there is a limited tidal window but also it would be a shame not to have time to enjoy the Holy Island and get back to Edinburgh. If you want to walk the Pilgrims Path barefoot on the sand and mud, the safe window is even shorter than using the causeway (which is passable to cars). Our
guidebook gives full details of how to work all this out.
In case it helps (quoting from Table 1 on page 7) if you give it only 5 days your daily walking mileages could be 16, 15, 13, 12 and 6 so you'd need some careful travel planning to get to Melrose and still walk 16 miles (or else you'd need to shift some miles from Day 1 to Day 2), and a lot of luck with the tides to visit, let alone enjoy Lindisfarne on Day 5.
Overall, if you can find an extra day, it would make for a much more relaxed walking holiday! Good luck anyway.
Jacquetta