@najme Design Forums are typically on Mondays 4-5pm UTC and Wednesdays 6-7pm UTC. You can read more about them here: https://wiki.openmrs.org/display/RES/Design+Forum
I suggest going here to request a design call: Propose a Design Forum Topic
I know that this Wednesday, we have a topic already on the agenda: Design Forum 2019-01-23: Architecture proposal: Modules and Verticals