Complex sentence: From 6 February 2014 Siderius temporarily replaced Renske Leijten who went on maternity leave, when Paulus Jansen resigned in April 2014 she became his permanent replacement on 14 May 2014.
Split into simpler sentences: From 6 February 2014 Siderius temporarily replaced Renske Leijten who went on maternity leave. When Paulus Jansen resigned in April 2014, Siderius became his permanent replacement on 14 May 2014.