Business Process as a Service (BPaaS) met a considerable proliferation and an exponential emergence as a new Cloud service for delivering complex and complete business applications. To better position themselves in the harshly competitive Cloud services market, BPaaS providers should offer to their clients, flexible services responding both to their functional and non-functional requirements. This article proposes a Reconfigurable BPaaS-based SaaS services Federation system (RBPF) allowing flexible support of user requirements changes. RBPF proposes to end-users minimal on the fly compositions whenever a reconfiguration is required. To do so, Boolean Satisfiability Problem-based algorithms are adopted to select the minimal reconfiguration. To reduce composition candidates research space, we propose new algorithms to group BPaaS services that are likely to compose within the same cluster. The clustering process leverages semantic Linked Open Data similarity measures to match service capabilities and identify composable ones.