An a/c age may add a little to an increase in technical delays, but any mechanical item will break down on and off.
Funny when left work tonight, H127 at Luton had an easyjet A319 being worked on, as it was Tech.
As previously posted on the extra stop yesterday on the MAN-AGP, it did indeed pick up some additional spares, plus an engineer and a replacement crew. This in an attempt to get the sick aircraft out of AGP before the night closure, alas a/c became serviceable after the airport closed.