A Software Ecosystem (SECO) refers to a collection of software products with some degree of symbiotic relationship. SOLAR is a Virtual Learning Environment (VLE) that enables the publication of courses and interaction with them among its various users. In this context, SOLAR SECO emerges, where diverse situations of software evolution and maintenance are part of its development process. The aim of this paper is to discuss the dynamic variability of SOLAR educational software ecosystem and software modeling. As an example, dynamic variability aspects of the feature model of SOLAR VLE discussion forum functionality were discussed, one of the most widely used services within SOLAR SECO. As a major conclusion of this work, we identified that the use of the contextual feature diagram allows the study of the dynamic aspects of a system, even more supported by tools to support automatic measurement collection.