#standardSQL switch does not work (BigQuery)

Several different #standardSQL queries generates errors:

for example:
'#standardSQL

select …
TIMESTAMP_TRUNC(ts_event , week) as week
(rest of query here which does work in BQ console)

generates an error :
3.17 - 3.35: Unrecognized function timestamp_trunc

Also, this type query:

'#standardSQL

with list as
(SELECT … (rest of valid standardSQL query here)

generates: Encountered " “WITH” "with “” at line 4, column 1. Was expecting:

yes, that’s a known issue, we’ll be fixing in the upcoming release
https://github.com/metabase/metabase/issues/3012 is the tracking issue

whats the ETA for the fix, so that standardSQL is usable? Google is moving away from legacySQL, joins are much slower in legacySQL and so on. For our use case MetaBase is not usable if only supporting legacySQL