The 500 foot rule doesn't apply:
(a) Landing and taking off
(i) Any aircraft shall be exempt from the low flying prohibitions in so far as it is flying
in accordance with normal aviation practice for the purpose of—
(aa) taking off from, landing at or practising approaches to landing at; or
(bb) checking navigational aids or procedures at,
a Government or licensed aerodrome.
(ii) Any aircraft shall be exempt from the 500 feet rule when landing and taking-off in
accordance with normal aviation practice or air-taxiing.
I've got an IMCR, but I won't fly if the forecast cloudbase is less than 1000 foot above ground for the whole journey. That's because the cloudbase may be (often is) lower than forecast, and it's rather boring anyway. It's fine being VFR on top, but most places I go don't have instrument approaches, and I really don't want to descend through cloud except on an instrument approach unless I know I'll be able to see by 1000 foot above anything to bump into.