"Beached" or half pay officers
Typos, he said with dignity, creep in at the darnedest places...
That's not precisely correct.
The RMN has a tradition of "loaning" active duty officers to allies like the Graysons. Those officers serve in the allied navy, draw pay there, and accrue seniority in that service. At the same time, however, they continue to accrue seniority in their current RMN ranks and are "double-dippers" for salary; the RMN continue to pay them a third of their normal Manticoran salary, plus they retain all of the nonsalaried benefits (medical service, personal and family insurance, etc.) of RMN personnel.
Half-pay officers are another matter entirely. A half-pay officer must accept reactivation when recalled or resign his commission; otherwise, he can do pretty much what he wants. (Many of these people hold merchant marine commissions, for example, and serve in the Manticoran merchant marine.) Technically, in time of war or declared national emergency, the Star Kingdom can require half-pay officers to return to active duty under penalty of law, but this has never truly been much of an issue in the SK's history to this point. It could prove a difficulty in the case of someone like a White Haven or a Harrington who, placed on half-pay by political enemies, accepted service with another navy and refused to return to Manticoran service (because those same political enemies remained in power) when recalled. And there are some sticky penalties for any half-pay officer's taking service with a designated "threat nation" (these are nations who are regarded as probable or potential enemies and so designated on an official list maintained by the Foreign Office). Obviously, as long as Grayson and the SK remain allies, however strained that relationship may be at the moment, Grayson isn't going to be listed as a "threat nation," which means that it would be legally impossible for Janacek to refuse to allow half-pay officers to serve in the GSN.