I think , 31/03/2018 was the date for 2018 journals metric ( impact factor, cite score .......)
I was assuming the same date would be for annual value. But today , I received one mail from Elsevier regarding the cite score , where it is mentioned that new annual value has been fully reached by June 2019.
Although the impact factors (Clarivate Analytics) are not yet available, it is already possible to review the Scopus metrics (CiteScore and SJR). You must search by title.
There is usually a couple of weeks gap between cite score and IF release dates. Scopus just released the cite scores 3-4 days ago, so IFs should be released somewhere around mid-june this year. Previously, the IFs are known to be released towards the end of June following the Cite score release from Scopus.
Hello, It will be released between 25 June-01 July. It will be better to submit article before 25 June to open access journal with no/little fee if you know that journal is going to have an impact factor in the coming WoS citation report.
Both, Web of Science - Clarivate Analytics (impact factor) and Scopus (SJR and citescore) publish their results in the second half of June of each year.
Please notice that SJR (Scimago) consolidated Journal metrics for 2018 are already available since a few days ago. As for JCR (Clarivate), it is quite possible that it will be released for the end of June (as happens almost every year).