I am not in MBB, but in one of the big 4 consulting firms and I know plenty of BA Golds and GGLs in our firm, in their mid to late 20s.
It depends on the particular client or project you end up on, but I do know of a few quite junior people who travel in J longhaul pretty much every week or at least fortnightly, especially if the client is in a country where our firm may have a smaller footprint. Popular client destinations seem to include South Africa, ME (especially Dubai) and HKG. Our US firm is huge so it's less usual to end up on a US engagement where weekly travel is needed.
The consulting skills needed for travel can be anything from business strategy, digital strategy, org design, technical implementations, cyber advisory, tax advisory, financial advisory, natural resources, property - in fact all sorts of things!
But I do also see a lot of very burnt out people who haven't hit 35 yet
