Not quite just yet:
The LTS upgrade window only opens after the first point release of 26.04.1.
It’s essentially the same, give or take a few release upgrader bugfixes, if any.
So long as you ensure that they stick to the official sources and tools, there shouldn’t be any problem upgrading; it’s pretty straight forward. Maybe just have a look at the upgrade notes to get an idea what not to do or to at least avoid if at all possible, when you install it and when they run it.
https://documentation.ubuntu.com/desktop/en/latest/how-to/upgrade-ubuntu-desktop/#upgrade-ubuntu-desktop
In essence, 3rd party package sources, such as PPA or upstream vendor package repositories, should be avoided at all costs; they are what breaks release upgrades, mostly.
You may also want to consider setting up an Ubuntu Pro account for or with them, which is free for personal use on up to five machines, so they get ESMApps security support for the universe component of the Ubuntu repository, kernel livepatching being the cherry on top.