Not sure there is enough spare space at Midland Road to deal with the unit without affecting FL significantly.Neville Hill to Midland Road depot, good road access, or even back to Doncaster depot over night, may still take a few nights and stops in loops to get it there, but again Doncaster Iep depot has good road access.
Doncaster is easily do-able overnight on skates
Skates: given 800 axle loads; 25mph on plain line and 3mph over low (<= 30mph) speed s&c.