I would guess A/C change is possibly for maintenance reasons as although there is a Spanair techie at MME what one man can do is limited ie no huge range of spares. Toy town International, Airbridge ha ha! Lucky to get a bus if stuck out on stand 1 in the rain. Usually the charters are a short walk from the terminal.
R23 is usually used but in light winds the option for landing traffic on 05 is available, subject to traffic, as you come in straight from GASKO.