These at MK give out wheelchair Return Times because their entry is not accessible:
Space Mountain
Jungle Cruise
Big Thunder Mountain RR
Small World (sometimes they have guests use the line to the point where it’s not accessible)
The Return Time is based on the current wait time in the regular line, minus 10 minutes. So, if the wait is 65 minutes, the Return Time will be 55 minutes in the future. Our experience (most recent November 2018) was paper tickets, not added to Magicband.
If you have a Fastpass for those attractions, you will usually be told to scan your ticket/Magicband and will still usually be given a ticket. The time on the ticket will be the current time, so you can go right in. It’s the same process if the current wait time is 15-20 minutes or less
Spaceship Earth boarding for guests with mobility devices is at the exit. There is a large waiting area and a large space for parking
ECV and other mobility devices.
They usually only give out Return Time tickets when the wait in the regular Standby line is very long or the waiting /parking areas are full.