[Opm] SHUT functionality in 2019.04

[Lex Rijkels]

Dear OPM community,
Has the SHUT functionality maybe changed in version  2019.04 of Flow? I am
running a simple well test forecast and my well does not react to:
WELOPEN
  WELLNAME SHUT /
/

It simply continues producing. It does stop with STOP (but then I lose the
reported FBHP) or a rate constraint of 0.
Have I missed something in the use of SHUT?
Thanks for your help,
Kind regards,
Lex Rijkels