Is there some way to add a custom message to the maintenance mode page?
Essentially, just to inform and reassure users. You know, “maintenance until 12pm at the latest, as we upgrade to the latest version. Thank you for your patience - the admin team” or something along those lines.
If this isn’t already a part of the maintenance mode feature at the moment, then consider this to be a suggestion to add this.
Maybe a page in the admin settings for maintenance mode, where the admin can turn on maintenance mode and include an announcement-style text box that gets shown on the maintenance page.
Because it’d be very useful to be able to clearly signal to users that, yes, this is scheduled maintenance and give them actual times, so they know how long to expect it to be down and why, and just a space for admins to give their grovelling apologies. 