Just wanted to know when or if there is a timeline when classic experience will stop working completely or no longer an option?
As most of our sites are migrated from SharePoint on-prem (SP2013) to SPO, we keep the classic experience for easy of user experience transition. We have no problem switch to modern experience but there are quite a few operations required by business not functioning in modern experience. e.g. for one, new form does not launch in documents library where metadata is required for upload