I worked in Financial Services for Kienbaum Mangement Consultants about 10 years ago (now Kienbaum Consutants International).
Three parameters are relevant.
1. Working at the client. Travelling is obviously on top. Very often at this time first flight in on Monday, last or second last flight out on Friday). And yes, "face time" /"window dressing was and for sure is still a topic depending on the manager and or director ;-( sad, but unfortunately usually true
2. Pitches. Pitches on top or even alone may be very time consuming, esp. for big tickets.
3. Seniority level. The more senior, but usually only from principal onwards, the more you can decide over your time.
Usually we were roughly from 9am to 9pm at the client. But hardly any work over the weekend.
Hope it helps, but it all depends on the firm, office and culture (of the acting people)...