<p>In high-demand knowledge-intensive IT workplaces, sustaining employee innovation amid rising job pressures is increasingly critical. Anchored in the Job Demands-Resources, Conservation of Resources, and control theory, this study explores the influence of work overload on employees' innovative work behavior, incorporating detachment from work as serial-mediator, workplace flexibility and cognitive flexibility as parallel-mediators, while job autonomy acts as a boundary condition that moderates the effects of flexibility on innovation. Data from 630 IT professionals were analyzed using PLS-SEM and Importance-Performance Map Analysis (IPMA). Findings indicate that work overload exerts a positive direct effect on IWB and an indirect effect through detachment from work and workplace flexibility. Detachment from work plays a crucial serial mediating role by enhancing workplace flexibility, which positively influences IWB. Surprisingly, cognitive flexibility did not exhibit a significant direct or mediated effect. Job autonomy moderates the relationship between workplace flexibility and innovative work behavior, though unexpectedly, the effect is stronger at lower autonomy levels. Cognitive flexibility remains consistently influential, regardless of autonomy levels. Importance-Performance Map Analysis identifies work overload as the most influential predictor, while cognitive flexibility is noted as underperforming. These insights underscore the value of integrating innovation and flexible systems management such as autonomy-supportive environments and recovery-supportive cultures to transform stressors into innovation enablers. The study contributes theoretically and practically to managing innovation in dynamic digital work contexts.</p>