The doubling of letters in LL.B., LL.M., LL.D. is because these degrees are in laws, not law. The doubled sign indicates the Latin plural (genitive case) legum as opposed to the singular (genitive case) legis. Abbreviations for the degrees in surgery Ch. B. and Ch. M. are from Latin chiruguriae and often indicate a university arrangement patterned after Scottish models. The combination of M.B. with Ch. B. arose from a need to graduate the students at the bit of year allocated to graduation rituals, but the legal inability to confer the M.B. before they had been properly approved by professional regulatory bodies. Thus the Ch. B. was conferred first, and the M.B. was conferred later, after registration, and without ceremony. In recent times the two have come to be conferred together and are widely (mis)understood to constitute a single degree.
This timetable is only approximate, however, as students in accelerated programs can sometimes earn a bachelor's degree in three years or, on the other hand, a particular dissertation activity might take four or Criminal Justice Degree more years to complete. In addition, a graduate may wait an indeterminate continuance between degrees before candidacy in the hard by level, or even an additional period at a akin already completed. Therefore, there is no time-limit on the accumulation of academic degrees.