Regulations may provide for circumstances in which a practitioner—
(a)whom a Local Health Board is investigating in order to see whether there are grounds for exercising its powers under section 107, 108 or 110,
(b)whom a Local Health Board has decided to remove from a list under section 107 or 108, or contingently remove under section 108, but who has not yet been removed or contingently removed, or
(c)who has been suspended under section 110,
may not withdraw from a list in which he is included.