What does recall means in this context? De-energizing the superconductor and shipping it back? Seems like a waste and a planning nightmare.
Remember, cryostats are like Russian dolls suspended on torsion wire. You want the mass of the metal inside to be as low as possible because it forms cold bridges to the outside world and increases the boil-off rate. Quenches should not happen once the magnet leaves the factory, but until that point it's not uncommon for a machine to have several "training" quenches as the (typically NbSn or NbTi) superconducting wire effectively anneals in place. A fixable giant hole in the top (with a graphite, insulating series of bursting discs) is the approach usually taken.
A surprising amount of maintenance can occur while the magnets are cold and energized. My armchair-uniformed-guess is that they can replace the not-always-working relief path without venting.