We can use any public car park around LHR (including short term)and BA will reimburse any parking fees ...
fly12345, are you absolutely sure about that? The instructions I have seen, dated 18 March, clearly state the following:
If the regular crew car park becomes full, .... [you] may park in any Long-Stay car park at LHR and claim back the cost of this parking. You must have a receipt to do this. (Please note that this specifically excludes Short-Stay car parks – like the NCP facility directly beside T5)