ESF BHS reserved list

My son attended beacon hill Y2 interview last month and just received an email saying that his interview was successful but the school has reached its immediate enrolment capacity and they are unable to offer him a place at this time due to enrollment capacity. My child will remain active on the reserve list until six months from now and after which he may be required to be re-interviewed.
Can anyone share your experience please Is the chance getting an offer within 6 months slim? The school office refused to answer me about his position in the list. We don’t have siblings priority but we do have a foreign passport. Thanks in advance.