FA Solutions Senior Implementation Manager interview questions

Two interviews two weeks apart which went very well. I got on well with the interviewers and was excited by the prospect of working with the firm. Asked to complete a technical assessment which I submitted in good time. Lost the role I initially applied for to an internal applicant. Put myself forward for a less senior role they had advertised which was accepted by all except CEO...waited another two weeks to receive good news that I had been approved for the role and to attend their offices for introductions the next day. Then received a further notification that evening that they had changed their mind last minute with no explanation or apology. All-in-all the whole process from initial interview to acceptance and sudden reversal took six weeks, Had a great experience with the interviewers but was kept waiting a long time and to then have a job dangled in front of me and then pulled away without any explanation was unfair and unprofessional. Very disappointing and demoralising.