ICU 66.1 only includes IANA time zone data tzdata2019c:
https://github.com/unicode-org/icu/blob/maint/maint-66/icu4c/source/data/misc/zoneinfo64.txt#L8
Upstream tzdata2020a was released to address the prior incorrect assumed temporary reversion of DST in Morocco due to Ramadan (eggert/tz@f9aacaf).
ICU merged unicode-org/icu@a951ab5 and released updated .res files for 2020a about 9 days ago. Unless the data files are manually updated and a new release is cut, users in Morocco and Intl API usage with zone Africa/Casablanca will see the time off by an hour between May 24th and May 31st.
ICU 66.1 only includes IANA time zone data
tzdata2019c:https://github.com/unicode-org/icu/blob/maint/maint-66/icu4c/source/data/misc/zoneinfo64.txt#L8
Upstream
tzdata2020awas released to address the prior incorrect assumed temporary reversion of DST in Morocco due to Ramadan (eggert/tz@f9aacaf).ICU merged unicode-org/icu@a951ab5 and released updated
.resfiles for 2020a about 9 days ago. Unless the data files are manually updated and a new release is cut, users in Morocco andIntlAPI usage with zoneAfrica/Casablancawill see the time off by an hour between May 24th and May 31st.