It seems like Will & Grace’s creative team could have easily just pushed Martin’s appearance until next season in order to allow for Alan Arkin to possibly find a hole in his schedule to fit a Will & Grace episode shoot, but perhaps that angle was also looked into.
Arkin might just be really busy and Grace might just really need her dad soon.
In an interesting and possibly disappointing-to-some twist, Will & Grace will have to give Grace’s father a new face for his return in an upcoming episode, with Debra Messing relaying Alan Arkin’s busy schedule kept him from returning to the NBC sitcom for a second round of family fun.