Altogether, until May 1, 2024, 31 students were involved in the bilingual longitudinal project. Statistical analysis presented here was carried out in March 2024; as a result, data from the May 2024 data collection wave are not included in this analysis. The sample analysed in this volume included the 2020 and 2021 cohorts, for whom the first data collection wave took place in September 2020 and 2021, respectively, and the second data collection wave was organised in May 2022 and 2023. As is often the case with longitudinal studies, a significant problem was encountered due to subject drop-out and/or non-compliance. Non-compliance in this context meant that subjects did not exactly follow instructions, which may have led to data loss or irrelevant data. Table 7 shows the number of students whose data could be used in the present study.

Table 7 also shows the number of students with English as their B or C working language. As can be seen, C English students outnumbered B English students in the sub-sample, but statistical procedures can compensate for the disparity.