There is apparently a graph out there (or perhaps just data) that shows the decay curve of time released prolixin decanoate (fluphenazine decanoate which is administered by deep intramuscular injection. It apparently (and unsurprisingly) takes a number of hours from injection to maximum blood level, and a number of more hours to decay to the level that provides the therapeutic effect. During this rise and decay period, there are apparently substantial impairment effects that it has--although this description isn't very detailed about those impairment effects.
I am not having much luck finding that information on the rise and decay characteristics.
UPDATE: Thanks to the reader who pointed me in the right direction: R. H. Mindham, "Assessment of drugs in schizophrenia. Asessment of drug-induced extrapyramidal reactions and of drugs given for their control," Br J Clin Pharmacol. 1976 June; 3(3 Suppl 2): 395–400, available here for free. It indicates that the maximum effect of the unwanted side effects (the ones that make it hard to walk a line, or do other tasks involving coordination) is three to five days after injection.