I am about to change my ISP, currently I have 50/50 symmetric, I plan to migrate to 200/200.
What should I do to get my node to update and take my new bandwidth?
It will always use as much as it needs (if that much is available), so you do not have to do anything. Currently, there is no benefit in having a better connection than 50/50. You won’t get more ingress with 200/200
If change in ISP would lead to change in router then make sure your port is forwarded on this new ISP. No-IP should take care of change in IP.
If they ISP replaces your router, be sure to re-forward the ports as well.