As per the information given on the below link, which says that journals that are initially evaluated and included in the Emerging Sources Citation Index (ESCI), will undergo more in-depth editorial review to be included in the Science Citations Index (SCI) or Social Science Citations Index (SSCI). However, timing for ESCI evaluation will follow Clarivate Analytics' priorities for expanding database coverage, rather than the date that journals were submitted for evaluation. I wonder if someone could explain what are the Clarivate Analytics' priorities??
(http://editorresources.taylorandfrancisgroup.com/what-is-the-emerging-sources-citation-index/)