My guess is that this is related to the later question about potential punishment. All questions need to be addressed by your husband to his attorney, not by you to lawyers on their computers who know nothing about the case.
Excludable time usually refers to time that is not counted under Rule 600 (the speedy trial rule) because of delay caused by defense motions and defense requested continuances. Your husbands attorney can explain.
“Excludable time” is technically defined in Rule 600(C) as the period of time between the filing of the written complaint and the defendant's arrest, provided that the defendant could not be apprehended because his whereabouts were unknown and could not be determined by due diligence. It can also refer to any period of time for which the defendant expressly waives Rule 600; and/or such period of delay at any stage of the proceedings as results from the unavailability of the defendant or the defendant's attorney or any continuance granted at the request of the defendant or the defendant's attorney.