I hope you have already cut the holes and this bit of advice is too late.
That looks difficult to get started. Once you have a complete round cut going, it should self-center and go smoothly. I would tack a thin piece of pine on there, 6mm or so, drill the pilot holes through the pine from the inside and see if the hole saw can get a start in the pine. Once you have an uninterrupted cut going it should settle down and run smoothly. once the hole is through the pine and into the boat, you can get the pine out of the way. Whatever you do, don't do what I do and forget to drill in short bursts so as not to overheat the hole saw and ruin the temper. Once overheated, they can be sharpened well enough for soft wood, but cutting hard wood with a soft saw is slow work. Something I have not tried, but will next time, is to drill a small hole near the inside edge of the hole once it is down a few mm. When using a plug cutter, it goes much easier if the edge of the hole breaks into the adjacent hole enough to let the chips out. A hole saw might also benefit from a 'chip drain'.
It should be difficult to spend time within 2m of anyone else on a bicycle. Gathering on a beach is probably not allowed, but there isn't a more difficult place for a virus to survive than hot sand with all the solar UV.
This is the Johns Hopkins map that is updated frequently showing the status of the virus. It is probably the most up to date and accurate information available. The daily increase tab on the small map in the lower right corner will be interesting to watch.