Nintendo has confirmed an upcoming spot of network maintenance which could have a minor impact on Switch's online services.
On Monday 20th April from 6pm - 8pm PT (that's 3am - 5am the following morning CEST), maintenance is planned for the "distribution of update data". What that means exactly is unclear, although Nintendo notes that "during the maintenance window, network services may be unavailable".
We should point out that this doesn't necessarily mean we'll see the next major system firmware update or anything similarly exciting appear once the maintenance is over. Still, it's worth keeping the date in mind and planning any online gameplay or eShop browsing around those times.
The last firmware update to arrive came at the beginning of last month, taking the system to Version 9.2.0. The changes? Lots of lovely stability.