German to English Social Sciences Psychology CBT to help an anxious person return to work

The patient has been undergoing therapy to overcome the social anxiety she suffers from at work. Now she is reaching the end of the treatment, and is being gradually reintegrated into her company.

Die Sitzungen 17 bis 19 **erfolgten begleitend zum Wiedereinstieg alle 2 Wochen.** In den ersten 2 Wochen des Wiedereinstiegs lag die Arbeitsdauer bei 2 h täglich, wobei alle 2 Wochen die Tagesarbeitszeit um 2 h erhöht wurde, bis schließlich in der 5. Woche der volle Arbeitsumfang von 6 h täglich erreicht wurde.

My draft:
Sessions 17-19 involved a guided return to work every 2 weeks. In the first 2 weeks, she worked 2 h per day, and every 2 weeks the working time per day was increased by 2 h, until finally, in week 5, she achieved the full day's work of 6 h.

But I can't really understand the first bit. It doesn't seem that she returned to work every 2 weeks (which would not be very helpful), but that she is going to work for the whole week, just gradually increasing the number of hours. So what is it that is happening "every 2 weeks"? That she is being "guided" by the therapist? It's unclear from the context just what that entails. For sure the number of hours increases every 2 weeks, but I'm not sure that is what is referred to in the sentence I am querying.

Thanks!