(1) Except where regulations otherwise provide, a person shall be disqualified for receiving any benefit under Part 2 (including any increase of benefit) for any period during which that person -

(a) is absent from the State, or

(b) is undergoing, imprisonment or detention in legal custody.

(1A) A person shall not be regarded as undergoing detention in legal custody for the purposes of entitlement to disability allowance while the person is detained for treatment pursuant to -

(a) an admission order or renewal order made under the Mental Health Act 2001,

(b) an order made under section 38 of the Health Act 1947,

(c) an order made under section 4 or section 5 of the Criminal Law (Insanity) Act 2006,

(d) an order made under section 17 of the Lunacy (Ireland) Act 1821, or

(e) an order made under section 2 of the Trial of Lunatics Act 1883.

(2) Except where regulations otherwise provide, where any benefit under Part 2 to which a person is entitled includes an increase in respect of a qualified adult, that increase shall not be payable for any period during which the qualified adult -

(a) is absent from the State, or