IT went smooth for me. I update from Steam. The first update was quick. When FS2020 was started, I went to the Content Manager and updated some but did not take all of the updates. Some of the airport updates were quite large and I did not want them that bad.
One this to note about the updates for FS2020. The World Updates seem to be mostly scenery and objects that get updated. But not much of the code. So it does not seem to break the add-ons. The Sim Updates are where coding gets changed, so those are where it might have an impact.
Keep flying and have fun!