Generally an average workweek is 50-55 hours.
Starting hours are as flexible as ending hours, unpaid overtime extending all the way to and including all nighters without promise of pay or an improvement to any bonus structure.
We are expected to work 8.30-5.30, but I usually do more than 9 hours. We can WFH, but most do 4+ days in the office. The company is pretty flexible where I might have commitments after work or medical appointments - no one is really marking attendance. We are regulated by utilisation rates which are calculated from chargeable time on our WIP per person.
Hours are quite standard for the industry. The number of hours worked are very dependent on the engagements you have been placed on/volunteered for. Typically, work will be more demanding towards the beginning of an engagement and calm down before you are required to join a new engagement.