What can be bought back, and up to what limit

Worked example

Three years of study, eight quarters available

A 44-year-old adviser completed a master's degree in five years, two of which produced no quarter at all. She believes she can buy back the twenty corresponding quarters. The shared ceiling stands in the way: twelve quarters at most, all grounds combined. Since she also has two incomplete calendar years at the start of her career, those four quarters are charged to the same envelope. Eight quarters therefore remain available to her under the study ground.