In terms of competitiveness, Business-IT Alignment (BITA) is still a crucial challenge for business leaders and CIOs, especially in the context of Digital Transformation and time-to-market challenges. Core Operational BITA can be seen as a projection of BITA to the Enterprise Information System perimeter, i.e., the operational alignment between the business processes and supporting IT. It is a major source of issues (e.g., strong couplings, maintenance costs, technical debt, slow adaptation). These cause a misalignment and thus contribute to the well-known Business-IT Gap. In this paper, we review the current state of this operational alignment in the context of Enterprise Architecture (EA) i.e. between the Business Process layer and the Application layer. Our analysis focuses on the models used at the Business Process and Application layers, the existing or potential links between these layers, and the use of these links to carry out a core operational alignment and facilitate the detection of potential divergence points. As a result, we notably outline some current limitations, such as modelling disparities, misuse of links between the two layers and an under-coverage of real alignment processes. We also discuss some lessons learned and future challenges, mainly around modelling needs and consistency management between the two considered layers.